https://hfunderground.com/wiki/index.php?title=Special:Contributions/SV1XV&feed=atom&limit=50&target=SV1XV&year=&month=HFUnderground - User contributions [en]2024-03-29T01:06:57ZFrom HFUndergroundMediaWiki 1.16.5https://hfunderground.com/wiki/index.php/Chris_SmolinskiChris Smolinski2023-09-07T08:23:13Z<p>SV1XV: </p>
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<div>[[File:ChrisSmolinski.jpg|right|250px]]<br />
Silly Rabbits.<br />
<br />
From 2001 to 2009, Smolinski worked in Karl Rove's office, leading the efforts in the weather control department.<br />
<br />
==See also==<br />
* [[User:ChrisSmolinski]]<br />
<br />
[[Category:People]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:ChrisSmolinski.jpgFile:ChrisSmolinski.jpg2023-09-07T08:22:10Z<p>SV1XV: Chris Smolinski (2022)</p>
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<div>Chris Smolinski (2022)</div>SV1XVhttps://hfunderground.com/wiki/index.php/Alice_BranniganAlice Brannigan2022-08-15T13:17:06Z<p>SV1XV: </p>
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<div>[[File:Tom K2AES.jpg|thumb|right]]<br />
'''Alice Brannigan''' was a pen name used in the 1980s by [[Popular Communications]] editor [[Tom Kneitel]], K2AES, for some of his articles in the magazine.<br />
<br />
[[Category:People]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Judica-Cordiglia_brothersJudica-Cordiglia brothers2022-08-07T12:37:03Z<p>SV1XV: </p>
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<div>[[File:Judica Cordiglia brothers.jpg|thumb|right|The Judica-Cordiglia brothers circa 1960]]<br />
[[Image:Judica-Cordiglia today.jpg|thumb|right|The Judica-Cordiglia brothers today]]<br />
'''Achille''' (born in Turin, 1933-2015) and '''Giovanni Battista''' (born in Erba, 1939) '''Judica-Cordiglia''' (or '''Judica Cordiglia''') are two former [[amateur radio]] operators and the source of some of the most dramatic and controversial claims of lost cosmonauts in the 1960s.<br />
<br />
In the late 1950s the brothers set up their own experimental listening station just outside of Turin, a place they named Torre Bert, in a disused German bunker. Working with scavenged and improvised equipment they were able to successfully monitor transmissions from the Soviet Sputnik program and Explorer 1, the first American satellite. Their receptions included telemetry, voice recordings, and visual data.<br />
<br />
In the 1960s, the brothers claimed to have recorded radio communications from secret Soviet Union space missions, including the sounds of one of these secret cosmonauts dying. The brothers claimed that the first of these recordings was made on 28 November 1960, when the Bochum space observatory in West Germany was said to have intercepted radio signals from what appeared to be a satellite. After about an hour of listening to static, the brothers recognised an SOS signal that seemed to be moving away from the Earth. In addition, they claimed to have recorded the voice of a woman, who was returning to Earth in May 1961; in the recording she is said to have cried that "she was burning".<br />
<br />
In 1964 they won the TV quiz ''Fiera dei Sogni'' (''The Fair of Dreams''), a quiz that enabled them to visit NASA. <br />
<br />
The brothers were the subject of a 2007 documentary called ''I pirati dello spazio'' (Pirates of space). An article on the brothers, recordings and lost cosmonauts was published in the March 2008 issue of the science-sceptical magazine ''Fortean Times''. A sympathetic dramatisation of the brothers' story was broadcast on BBC Radio 4 in May 2009 ("Listen Up", by Glen Neath).<br />
<br />
Achille is now a cardiologist, while Giovanni Battista assists the Italian police with phone-tapping in criminal investigations.<br />
<br />
==See also==<br />
<br />
* [[The Lost Cosmonauts]]<br />
* Dossier Sputnik. "...Questo il mondo non lo saprà..." di Judica Cordiglia Achille - Judica Cordiglia G. Battista, 2006 ISBN 8890202785 ISBN 9788890202780<br />
<br />
==External links==<br />
* [http://www.lostcosmonauts.com/default.htm Judica-Cordiglia brothers' website]<br />
* [http://www.judicacordiglia.it Italian website]<br />
* [http://www.aerospaceweb.org/question/conspiracy/q0235a.shtml ''Readers' Digest'' Article]<br />
* [http://www.svengrahn.pp.se/trackind/Torre/TorreB.html Site debunking the brothers' claims]<br />
* [http://www.forteantimes.com/features/articles/1302/lost-in-space.html ''Fortean Times'' Article]<br />
* [http://www.zenit.to.it/eng/prod_doc_pirati_dello_spazio.html ''I pirati dello spazio'' (''Space Hackers'')] - TV documentary by A. Bernard, E. Cerasuolo, P. Ceretto - Zenit Arti Audiovisive, 2007<br />
<br />
<br />
{{CC-BY-SA-WP|Judica-Cordiglia_brothers}}<br />
<br />
<br />
[[Category:Radio esoterica]]<br />
[[Category:People]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:Judica_Cordiglia_brothers.jpgFile:Judica Cordiglia brothers.jpg2022-08-07T12:33:41Z<p>SV1XV: </p>
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<div>==Summary==<br />
<br />
The Judica-Cordiglia brothers, Achille (1933–2015) and Giovanni Battista (1939–), radio amateurs and pioneer utility listeners of Turin, Italy. <br />
<br />
Source: [[https://caraltalks.files.wordpress.com/2014/05/judica-cordiglia-brothers.jpg]]<br />
<br />
Republished on Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Judica-cordiglia-brothers.jpg<br />
<br />
==Licensing==<br />
<br />
Public domain photograph, copyright of simple photographs in Italy expires after 20 years.<br />
<br />
<br />
[[Category:People]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:Judica_Cordiglia_brothers.jpgFile:Judica Cordiglia brothers.jpg2022-08-07T12:33:04Z<p>SV1XV: </p>
<hr />
<div>The Judica-Cordiglia brothers, Achille (1933–2015) and Giovanni Battista (1939–), radio amateurs and pioneer utility listeners of Turin, Italy. <br />
<br />
Source: [[https://caraltalks.files.wordpress.com/2014/05/judica-cordiglia-brothers.jpg]]<br />
<br />
Republished on Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Judica-cordiglia-brothers.jpg<br />
<br />
Public domain photograph, copyright of simple photographs in Italy expires after 20 years.<br />
<br />
<br />
[[Category:People]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:Judica_Cordiglia_brothers.jpgFile:Judica Cordiglia brothers.jpg2022-08-07T12:32:41Z<p>SV1XV: The Judica-Cordiglia brothers, Achille (1933–2015) and Giovanni Battista (1939–), radio amateurs and pioneer utility listeners of Turin, Italy.
Source: https://caraltalks.files.wordpress.com/2014/05/judica-cordiglia-brothers.jpg
Republished on Wiki</p>
<hr />
<div>The Judica-Cordiglia brothers, Achille (1933–2015) and Giovanni Battista (1939–), radio amateurs and pioneer utility listeners of Turin, Italy. <br />
<br />
Source: https://caraltalks.files.wordpress.com/2014/05/judica-cordiglia-brothers.jpg<br />
<br />
Republished on Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Judica-cordiglia-brothers.jpg<br />
<br />
Public domain photograph, copyright of simple photographs in Italy expires after 20 years.<br />
<br />
<br />
[[Category:People]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:Ary_Boender.jpgFile:Ary Boender.jpg2022-08-07T12:29:18Z<p>SV1XV: </p>
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<div>Ary Boender of WUN and UDXF, source: priyom-freenode-19/8/2015-7<br />
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[[Category:People]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2022-03-05T17:57:09Z<p>SV1XV: /* Solitary beacons and channel markers */ V</p>
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<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| '''5156.8''', 7038.2, 7041.8<sup>(23)</sup>, 8494.2, '''8497.8'''<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5342.0,<BR> 5466.0, 5590.0, 7611.0, 7714.0, 7727.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2022-02-13T16:24:42Z<p>SV1XV: /* Solitary beacons and channel markers */ bold</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| '''5156.8''', 7038.2, 7041.8<sup>(23)</sup>, 8494.2, '''8497.8'''<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| '''3227.0''', '''3657.0''', 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, '''5342.0''',<BR> 5466.0, 5590.0, '''7611.0''', 7714.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-11-10T03:50:48Z<p>SV1XV: /* Solitary beacons and channel markers */</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| '''5156.8''', 7038.2, 7041.8<sup>(23)</sup>, 8494.2, '''8497.8'''<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5342.1,<BR> 5466.0, 5590.0, 7611.0, 7714.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-11-10T03:41:26Z<p>SV1XV: /* Solitary beacons and channel markers */ +1</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| '''5156.8''', 7038.2, 7041.8<sup>(23)</sup>, 8494.2, '''8497.8'''<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5342.1,<BR> 5466.0, 5590.0, 7714.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-11-09T03:30:14Z<p>SV1XV: /* Solitary beacons and channel markers */ -1</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| '''5156.8''', 7038.2, 7041.8<sup>(23)</sup>, 8494.2, '''8497.8'''<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5342.1,<BR> 5466.0, 5590.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-11-09T03:28:40Z<p>SV1XV: /* Solitary beacons and channel markers */ +1</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| '''5156.8''', 7038.2, 7041.8<sup>(23)</sup>, 8494.2, '''8497.8'''<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5342.1,<BR> 5466.0, 5590.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 5342, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-09-03T02:47:12Z<p>SV1XV: /* Cluster beacons */ current L frequencies in bold</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| '''5156.8''', 7038.2, 7041.8<sup>(23)</sup>, 8494.2, '''8497.8'''<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5466.0, 5590.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 5342, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-09-03T02:44:58Z<p>SV1XV: /* Cluster beacons */ 2021 observations</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7039.0, <s>7509.0</s>, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
;; Notes<br />
<br />
* Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods. <br />
* The cluster on 3594.0 kHz seems to be inactive in 2021.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5466.0, 5590.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 5342, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-09-03T02:41:53Z<p>SV1XV: /* Cluster beacons */ 2021 observations</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, <s>7038.8</s>, 7508.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7039.0, <s>7508.9</s>, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5466.0, 5590.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 5342, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/International_Short_Wave_LeagueInternational Short Wave League2021-04-18T05:55:47Z<p>SV1XV: moved image</p>
<hr />
<div>[[Image:ISWL-logo.png|thumb|right|Logo of the International Short Wave League]]<br />
The '''International Short Wave League''' (ISWL) is radio society which was formed in Great Britain in 1946. Unlike most radio societies, the League effectively caters for members interested in both the [[Amateur radio]] and Broadcast Band [[DXing]]. Membership of the ISWL is open to both licensed radio amateurs and Short Wave Listeners (SWLs) world-wide. The International Short Wave League is run by volunteers who are elected by the Leagues members. <br />
<br />
All ISWL members can participate in the League's contest and awards programs. The awards are also available to non members and can be posted world-wide. In addition to radio amateurs and SWLs, clubs and other radio organisations may also join the League.<br />
<br />
The ISWL publishes a monthly journal called ''Monitor'', which is sent to members. It contains sections about Contests, HF operations, Airband, DX news,<br />
Short Wave Broadcast schedules, as well as occasional articles written by League members, relating to QRP, VHF operation, antennas etc.<br />
<br />
The International Short Wave League is affiliated to the [[Radio Society of Great Britain]].<br />
<br />
==HF/VHF nets==<br />
<br />
The ISWL holds regular nets throughout the week at various times and on various frequencies and all radio amateurs are welcome to participate whether ISWL members or not. The 80 and 40 meter SSB nets (3.5 and 7 MHz) are very active, in contrast to the CW and VHF nets. The club amateur radio callsigns [http://www.qrz.com/db/gx4bjc/ GX4BJC/A] and [http://www.qrz.com/db/mx1swl/ MX1SWL/A] can be operated by British (U.K.) licensed members on a rota basis for one month, from their own station's QTH and can be heard on many of the nets each week.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" <br />
|- style="background: #E7E7FF"<br />
! Day !! Mode !! UTC !! QRG (kHz)<br />
|-<br />
| Sunday || SSB || 15:00 || 7055 or 3685 <br />
|-<br />
| Sunday || SSB || 19:00 || 144270<br />
|-<br />
| Sunday || SSB || 20:30 || 1925<br />
|-<br />
| Monday || CW || 19:30 || 3563<br />
|-<br />
| Tuesday || SSB || 19:00 || 3700<br />
|-<br />
| Saturday || SSB || 10:30 || 3685<br />
|-<br />
| Sunday || SSB || 10:30 || 50270<br />
|-<br />
| Thursday || FM || 19:00 || 145500<br />
|-<br />
| Saturday || FM || 16:00 || 145500<br />
|-<br />
|}<br />
<br />
Special callsign '''GB75ISWL''' is on the air throughout 2021, to celebrate 75 years since the establisment of ISWL.<br />
<br />
==QSL Bureau==<br />
[[File:QSL GB75ISWL (2021).jpg |thumb |right |QSL GB75ISWL]]<br />
The ISWL operates a QSL Bureau of its own, which is well known for its fast through-put, with outgoing [[QSL]] cards cleared on an ongoing basis. There is a small annual fee for the use of the Bureau. The ISWL QSL Bureau is unique, in that all cards addressed to members are dispatched at the League's expense, with self-addressed and stamped envelopes not being required. Access to the QSL Bureau is only open to current ISWL members.<br />
<br />
The ISWL actively supports electronic [[QSL]] cards via [http://www.eqsl.cc/qslcard/ eQSL.cc] but does not support the [[American Radio Relay League|ARRL]] Logbook of the World.<br />
<br />
==References==<br />
<br />
* http://www.iswl.org.uk/internat.htm ISWL website<br />
* Alan Loveridge G-11901: "The art of QSL'ing", ''International Short Wave League''<br />
* [[Jerome S. Berg]]: "Listening on the short waves, 1945 to today", McFarland, 2008, p. 133<br />
<br />
[[Category:Radio societies]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:Sv1xv.jpgFile:Sv1xv.jpg2021-04-12T05:17:12Z<p>SV1XV: +cat</p>
<hr />
<div>SV1XV QSL card, for use on personal page.<br />
<br />
[[Category:Amateur Radio QSLs]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/User:SV1XVUser:SV1XV2021-04-12T05:16:08Z<p>SV1XV: /* Images */</p>
<hr />
<div>[[File:Sv1xv.jpg|left|150px]]<br />
This is Costas SV1XV.<br />
<br />
Please visit my website http://www.qsl.net/sv1xv<br />
and my blog http://sv1xv.blogspot.com<br />
<br />
I also have a collection of photographs and other images on http://www.ipernity.com/doc/777361 <br />
<br />
73<br />
{{clear}}<br />
<br />
==Interesting stuff==<br />
<br />
# [[DXing]]<br />
# [[SPEEDX]]<br />
# [[WUN]]<br />
<br />
==Beacons==<br />
<br />
# [[HiFER]]<br />
# [[High Frequency Beacon]]<br />
# [[Letter beacon]]<br />
# [[LowFER]]<br />
# [[Part 15 Beacons]]<br />
# [[Pictures of high frequency beacons]]<br />
# [[Radio beacon]]<br />
# [[Radio propagation beacon]]<br />
<br />
==Images==<br />
<gallery><br />
<br />
File:QSL GB75ISWL (2021).jpg<br />
<br />
</gallery><br />
<br />
{{clear}}</div>SV1XVhttps://hfunderground.com/wiki/index.php/User:SV1XVUser:SV1XV2021-04-12T05:15:18Z<p>SV1XV: /* Images */</p>
<hr />
<div>[[File:Sv1xv.jpg|left|150px]]<br />
This is Costas SV1XV.<br />
<br />
Please visit my website http://www.qsl.net/sv1xv<br />
and my blog http://sv1xv.blogspot.com<br />
<br />
I also have a collection of photographs and other images on http://www.ipernity.com/doc/777361 <br />
<br />
73<br />
{{clear}}<br />
<br />
==Interesting stuff==<br />
<br />
# [[DXing]]<br />
# [[SPEEDX]]<br />
# [[WUN]]<br />
<br />
==Beacons==<br />
<br />
# [[HiFER]]<br />
# [[High Frequency Beacon]]<br />
# [[Letter beacon]]<br />
# [[LowFER]]<br />
# [[Part 15 Beacons]]<br />
# [[Pictures of high frequency beacons]]<br />
# [[Radio beacon]]<br />
# [[Radio propagation beacon]]<br />
<br />
==Images==<br />
<gallery><br />
[[File:QSL GB75ISWL (2021).jpg|150px]]<br />
</gallery><br />
<br />
{{clear}}</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:QSL_GB75ISWL_(2021).jpgFile:QSL GB75ISWL (2021).jpg2021-04-12T05:14:22Z<p>SV1XV: +cat</p>
<hr />
<div>QSL card for special callsign GB75ISWL, used in 2021 by the [[International Short Wave League]].<br />
<br />
[[Category:Amateur Radio QSLs]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/User:SV1XVUser:SV1XV2021-04-12T05:13:21Z<p>SV1XV: /* Beacons */</p>
<hr />
<div>[[File:Sv1xv.jpg|left|150px]]<br />
This is Costas SV1XV.<br />
<br />
Please visit my website http://www.qsl.net/sv1xv<br />
and my blog http://sv1xv.blogspot.com<br />
<br />
I also have a collection of photographs and other images on http://www.ipernity.com/doc/777361 <br />
<br />
73<br />
{{clear}}<br />
<br />
==Interesting stuff==<br />
<br />
# [[DXing]]<br />
# [[SPEEDX]]<br />
# [[WUN]]<br />
<br />
==Beacons==<br />
<br />
# [[HiFER]]<br />
# [[High Frequency Beacon]]<br />
# [[Letter beacon]]<br />
# [[LowFER]]<br />
# [[Part 15 Beacons]]<br />
# [[Pictures of high frequency beacons]]<br />
# [[Radio beacon]]<br />
# [[Radio propagation beacon]]<br />
<br />
==Images==<br />
[[File:QSL GB75ISWL (2021).jpg|150px]]<br />
<br />
<br />
{{clear}}</div>SV1XVhttps://hfunderground.com/wiki/index.php/International_Short_Wave_LeagueInternational Short Wave League2021-04-12T05:12:15Z<p>SV1XV: /* HF/VHF nets */ QSL card</p>
<hr />
<div>[[Image:ISWL-logo.png|thumb|right|Logo of the International Short Wave League]]<br />
The '''International Short Wave League''' (ISWL) is radio society which was formed in Great Britain in 1946. Unlike most radio societies, the League effectively caters for members interested in both the [[Amateur radio]] and Broadcast Band [[DXing]]. Membership of the ISWL is open to both licensed radio amateurs and Short Wave Listeners (SWLs) world-wide. The International Short Wave League is run by volunteers who are elected by the Leagues members. <br />
<br />
All ISWL members can participate in the League's contest and awards programs. The awards are also available to non members and can be posted world-wide. In addition to radio amateurs and SWLs, clubs and other radio organisations may also join the League.<br />
<br />
The ISWL publishes a monthly journal called ''Monitor'', which is sent to members. It contains sections about Contests, HF operations, Airband, DX news,<br />
Short Wave Broadcast schedules, as well as occasional articles written by League members, relating to QRP, VHF operation, antennas etc.<br />
<br />
The International Short Wave League is affiliated to the [[Radio Society of Great Britain]].<br />
<br />
==HF/VHF nets==<br />
[[File:QSL GB75ISWL (2021).jpg |thumb |right |QSL GB75ISWL]]<br />
The ISWL holds regular nets throughout the week at various times and on various frequencies and all radio amateurs are welcome to participate whether ISWL members or not. The 80 and 40 meter SSB nets (3.5 and 7 MHz) are very active, in contrast to the CW and VHF nets. The club amateur radio callsigns [http://www.qrz.com/db/gx4bjc/ GX4BJC/A] and [http://www.qrz.com/db/mx1swl/ MX1SWL/A] can be operated by British (U.K.) licensed members on a rota basis for one month, from their own station's QTH and can be heard on many of the nets each week.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" <br />
|- style="background: #E7E7FF"<br />
! Day !! Mode !! UTC !! QRG (kHz)<br />
|-<br />
| Sunday || SSB || 15:00 || 7055 or 3685 <br />
|-<br />
| Sunday || SSB || 19:00 || 144270<br />
|-<br />
| Sunday || SSB || 20:30 || 1925<br />
|-<br />
| Monday || CW || 19:30 || 3563<br />
|-<br />
| Tuesday || SSB || 19:00 || 3700<br />
|-<br />
| Saturday || SSB || 10:30 || 3685<br />
|-<br />
| Sunday || SSB || 10:30 || 50270<br />
|-<br />
| Thursday || FM || 19:00 || 145500<br />
|-<br />
| Saturday || FM || 16:00 || 145500<br />
|-<br />
|}<br />
<br />
Special callsign '''GB75ISWL''' is on the air throughout 2021, to celebrate 75 years since the establisment of ISWL.<br />
<br />
==QSL Bureau==<br />
<br />
The ISWL operates a QSL Bureau of its own, which is well known for its fast through-put, with outgoing [[QSL]] cards cleared on an ongoing basis. There is a small annual fee for the use of the Bureau. The ISWL QSL Bureau is unique, in that all cards addressed to members are dispatched at the League's expense, with self-addressed and stamped envelopes not being required. Access to the QSL Bureau is only open to current ISWL members.<br />
<br />
The ISWL actively supports electronic [[QSL]] cards via [http://www.eqsl.cc/qslcard/ eQSL.cc] but does not support the [[American Radio Relay League|ARRL]] Logbook of the World.<br />
<br />
==References==<br />
<br />
* http://www.iswl.org.uk/internat.htm ISWL website<br />
* Alan Loveridge G-11901: "The art of QSL'ing", ''International Short Wave League''<br />
* [[Jerome S. Berg]]: "Listening on the short waves, 1945 to today", McFarland, 2008, p. 133<br />
<br />
[[Category:Radio societies]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/File:QSL_GB75ISWL_(2021).jpgFile:QSL GB75ISWL (2021).jpg2021-04-12T05:11:18Z<p>SV1XV: QSL card for special callsign GB75ISWL, used in 2021 by the International Short Wave League.</p>
<hr />
<div>QSL card for special callsign GB75ISWL, used in 2021 by the [[International Short Wave League]].</div>SV1XVhttps://hfunderground.com/wiki/index.php/International_Short_Wave_LeagueInternational Short Wave League2021-04-12T05:09:08Z<p>SV1XV: /* HF/VHF nets */ GB75ISWL</p>
<hr />
<div>[[Image:ISWL-logo.png|thumb|right|Logo of the International Short Wave League]]<br />
The '''International Short Wave League''' (ISWL) is radio society which was formed in Great Britain in 1946. Unlike most radio societies, the League effectively caters for members interested in both the [[Amateur radio]] and Broadcast Band [[DXing]]. Membership of the ISWL is open to both licensed radio amateurs and Short Wave Listeners (SWLs) world-wide. The International Short Wave League is run by volunteers who are elected by the Leagues members. <br />
<br />
All ISWL members can participate in the League's contest and awards programs. The awards are also available to non members and can be posted world-wide. In addition to radio amateurs and SWLs, clubs and other radio organisations may also join the League.<br />
<br />
The ISWL publishes a monthly journal called ''Monitor'', which is sent to members. It contains sections about Contests, HF operations, Airband, DX news,<br />
Short Wave Broadcast schedules, as well as occasional articles written by League members, relating to QRP, VHF operation, antennas etc.<br />
<br />
The International Short Wave League is affiliated to the [[Radio Society of Great Britain]].<br />
<br />
==HF/VHF nets==<br />
<br />
The ISWL holds regular nets throughout the week at various times and on various frequencies and all radio amateurs are welcome to participate whether ISWL members or not. The 80 and 40 meter SSB nets (3.5 and 7 MHz) are very active, in contrast to the CW and VHF nets. The club amateur radio callsigns [http://www.qrz.com/db/gx4bjc/ GX4BJC/A] and [http://www.qrz.com/db/mx1swl/ MX1SWL/A] can be operated by British (U.K.) licensed members on a rota basis for one month, from their own station's QTH and can be heard on many of the nets each week.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" <br />
|- style="background: #E7E7FF"<br />
! Day !! Mode !! UTC !! QRG (kHz)<br />
|-<br />
| Sunday || SSB || 15:00 || 7055 or 3685 <br />
|-<br />
| Sunday || SSB || 19:00 || 144270<br />
|-<br />
| Sunday || SSB || 20:30 || 1925<br />
|-<br />
| Monday || CW || 19:30 || 3563<br />
|-<br />
| Tuesday || SSB || 19:00 || 3700<br />
|-<br />
| Saturday || SSB || 10:30 || 3685<br />
|-<br />
| Sunday || SSB || 10:30 || 50270<br />
|-<br />
| Thursday || FM || 19:00 || 145500<br />
|-<br />
| Saturday || FM || 16:00 || 145500<br />
|-<br />
|}<br />
<br />
Special callsign '''GB75ISWL''' is on the air throughout 2021, to celebrate 75 years since the establisment of ISWL.<br />
<br />
==QSL Bureau==<br />
<br />
The ISWL operates a QSL Bureau of its own, which is well known for its fast through-put, with outgoing [[QSL]] cards cleared on an ongoing basis. There is a small annual fee for the use of the Bureau. The ISWL QSL Bureau is unique, in that all cards addressed to members are dispatched at the League's expense, with self-addressed and stamped envelopes not being required. Access to the QSL Bureau is only open to current ISWL members.<br />
<br />
The ISWL actively supports electronic [[QSL]] cards via [http://www.eqsl.cc/qslcard/ eQSL.cc] but does not support the [[American Radio Relay League|ARRL]] Logbook of the World.<br />
<br />
==References==<br />
<br />
* http://www.iswl.org.uk/internat.htm ISWL website<br />
* Alan Loveridge G-11901: "The art of QSL'ing", ''International Short Wave League''<br />
* [[Jerome S. Berg]]: "Listening on the short waves, 1945 to today", McFarland, 2008, p. 133<br />
<br />
[[Category:Radio societies]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2021-04-12T04:59:59Z<p>SV1XV: /* Solitary beacons and channel markers */ update V, L</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3657.0, 4031.0, 4205.0, 4338.0, 4977.0, 5094.0, 5466.0, 5590.0<br />
|-<br />
| align="center" | '''V (historic)'''<br />
| align="center" | <br />
| 3335.0, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, 5141.0, 5342, 6430.7, 6498.0,<BR> 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || '''5156.8''', 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2020-10-24T17:55:39Z<p>SV1XV: /* Solitary beacons and channel markers */</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3335.0, '''3657.0''', 4028.0, '''4031''', 4108.0<sup>(18)</sup>, 4150.0, '''4338.0'''. '''4977.0''', <BR>5094.0, 5141.0, 5342, '''5466.0''', 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/UVB-76_(The_Buzzer)UVB-76 (The Buzzer)2019-10-05T18:16:32Z<p>SV1XV: /* External links */ +1</p>
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<div>[[Image:UVB76 antenna.jpg|thumb|right|Satellite photo of UVB-76 transmitter in [[Povarovo]], [[Russia]].]]<br />
'''UVB-76''', (Now "ANVF", formerly "MDZhB" and "ZhUOZ") is the callsign of a HF radio station that usually broadcasts on the frequency [[Fixed/Mobile_bands|4625&nbsp;kHz]] on a USB (Upper Side Band) signal. It is known among radio listeners by the nickname '''The Buzzer'''. It features a short, monotonous buzz tone, repeating at a rate of approximately 25 tones per minute, for 24 hours per day. The station has been observed since around 1982.<sup>[1]</sup>. Until 2010, most voice transmissions in the Russian Monolit code signal were rare.<br />
<br />
The Buzzer has four callsigns: UVB-76, MDZhB (Mikhail, Dmitri, Zhenya, Boris), ZhUOZ (Zhenya, Ulyana, Olga, Zinaida), and ANVF (Anna, Nikolai, Vasily, Fyodor)<br />
<br />
==Normal transmission==<br />
[[Image:UVB-76-detail.png|thumb|right|A spectrum for UVB-76 showing the suppressed lower sideband.]]<br />
The station transmits a buzzing sound that lasts 0.8 seconds, pausing for 1–1.3 seconds, and repeating 21–34 times per minute.<sup>[1]</sup> One minute before the hour, the repeating tone is replaced by a continuous tone, which continues for one minute until the short repeating buzz resumes. Between 07:00 and 07:50 GMT the station transmits using lower power, when transmitter maintenance apparently takes place.<br />
<br />
The Buzzer has apparently been broadcasting since at least 1982 <sup>[1]</sup> as a repeating two-second pip, changing to a buzzer in early 1990.<sup>[2]</sup> <sup>[3]</sup> It briefly changed to a higher tone of longer duration (approximately 20 tones per minute) on January 16, 2003, although it has since reverted to the previous tone pattern.<sup>[4]</sup><br />
<br />
It is believed that the buzzer is not directly modulated but actually recorded by a active microphone, as there have been reports of hearing background chatter while the buzzer was on.<br />
<br />
==Malfunctions==<br />
Frequently, distant conversations and other background noises can be heard behind the buzzer: this suggests that the buzzing device is behind a live and constantly open microphone (rather than a recording or automated sound being fed through playback equipment) or that a microphone may have been turned on accidentally. One such occasion was on November 3, 2001, when a conversation in Russian was heard:<sup>[1]</sup> "Я — 143. Не получаю генератор." "Идёт такая работа от аппаратной." ("I am 143. Not receiving the generator (oscillator)." "There's some work on the hardware.")<br />
<br />
UVB-76 has become much more active as of 2010. In early June, many listeners also report that it simply stopped transmitting, although transmission resumed by June 6th, 2010. That same day, many listeners reported transmissions in Morse Code. Since the start of June 2010, the normal buzzing sound from UVB-76 has been replaced by a continuous high pitched noise, similar to that of a modem, with intermittent deeper tones like that of a foghorn.<sup>[5]</sup> Whether this is a malfunction or an intended change to the buzzing remains to be seen. On June 10, UVB-76 reportedly transmitted actual polytone data bursts followed by another Morse Code transmission. Several conflicting amateur reports on UVB-76's recent activities also date from June 2010.<sup>[6]</sup><br />
<br />
==Voice messages==<br />
Voice messages from UVB-76 were very rare, until 2010. There are six well-known recordings:<br />
<br />
* At 21:58 [[GMT]] on December 24, 1997, the buzzing abruptly stopped to be replaced by a short series of beeps, and a male voice speaking Russian announced: "Ya&nbsp;— UVB-76. 18008. BROMAL: Boris, Roman, Olga, Mikhail, Anna, Larisa. 742, 799, 14."<sup>[7]</sup> The same message was repeated several times before the beep sequence repeated and the buzzer resumed.<br />
* A similar voice message was broadcast on September 12, 2002, but with extreme distortion (possibly as a result of the source being too close to the microphone head) that rendered comprehension very difficult. This second voice broadcast has been partially translated as "UVB-76, UVB-76. 62691 Izafet 3693 8270."<br />
* A third voice message was broadcast on February 21, 2006 at 7:57 GMT. ([http://mikeandsniffy.co.uk/vlt/zz/S28_4625_07.57_21.2.06.mp3 recording of the third voice transmission]) Again, the speaking voice was highly distorted, but the message's content translates as: "75-59-75-59. 39-52-53-58. 5-5-2-5. Konstantin-1-9-0-9-0-8-9-8-Tatiana-Oksana-Anna-Elena-Pavel-Schuka. Konstantin 8-4. 9-7-5-5-9-Tatiana. Anna Larisa Uliyana-9-4-1-4-3-4-8."<sup>[8]</sup> These names are found in some Russian spelling alphabets.<sup>[9]</sup><br />
* The fourth transmission, on August 23, 2010, was broadcast at 13:35 UTC: "UVB-76, UVB-76. 93 882 NAIMINA 74 14 35 74. 9 3 8 8 2 Nikolai, Anna, Ivan, Mikhail, Ivan, Nikolai, Anna. 7 4 1 4 3 5 7 4"<br />
* The fifth transmission, this time with the callsign MDZhB, was transmitted on January 25, 2013, at 02:47 UTC: "MDZhB TERKA 0254 МDZhB ТЕRКА 0254 MDZhB OBYAVLENA KOMANDA 135 (command 135 announced)"<br />
* The sixth transmission, this time with the callsign ZhUOZ, was transmitted on December 15, 2015, at 16:28 UTC: "Zhenya, Ulyana, Olga, Zinaida. Zhenya, Ulyana, Olga, Zinaida. 92, 002, AGATU, 56, 88, 48, 32."<br />
* On March 2019, the station seemingly changed its callsign to ANVF (Anna, Nikolai, Vasily, Fyodor)<br />
<br />
==Equipment==<br />
The station uses Molniya-2M (PKM-15) and Molniya-3 (PKM-20) transmitters and a Viaz-M2 backup transmitter. The transmitter power is approximately 10&nbsp;kW and backup power is 2.5&nbsp;kW, which is used from 7:00 to 7.50 UTC. The antenna model is a horizontal dipole VGDSh (Nadenenko), height approximately 20&nbsp;m.<br />
<br />
==Location and function==<br />
The station's transmitter was located just outside Povarovo, Russia at 56°4′58″N 37°5′22″E, which is about halfway between Zelenograd and Solnechnogorsk and 40&nbsp;km northwest of Moscow, near the village of Lozhki. The location and callsign were unknown until the first voice broadcast of 1997.<br />
<br />
In September of 2010, the station was evacuated, the station transmitter was moved to the nearby city of Saint Petersburg, near the village of Kerro Massiv. This may have been due to a reorganization of the Russian military. Prior to August 9, 2015, the station is not transmitted from the Kerro Massiv transmitter site ("Irtysh") anymore, possibly due to a reorganization of the Russian military for the particular area which may cause the frequency to be used only in the Moscow Military District. At present, The Buzzer appears to be broadcast only from the 69th Communication Hub in Naro Fominsk, Moscow.<br />
<br />
Its purpose is unknown. One website claims the station is meant to "Transmit orders to the military units and recruitment centers of the Moscow military district." This is unconfirmed, and unlikely considering the station transmitted the simple buzz tone for at least 15 years before any words or numbers were broadcast. Because of the nature of the broadcast and the fact that its transmitter location is rumored to be a communications hub of the General Staff of the army,<sup>[10]</sup> UVB-76 is widely believed to be used to transmit encoded messages to spies, as is generally assumed for the many [[Spy Numbers Stations|numbers stations]] that populate shortwave frequencies. Transmitter sites for some numbers stations have been triangulated to military and/or intelligence installations in several countries, although no nation's government will confirm or deny the existence of the stations or their purpose. Another possibility is that the constant transmission of its characteristic sound is supposed to signal the availability, operation or alertness of some kind of installation, a kind of dead man's switch of a military or other installation, possibly for the Russian Dead Hand system.<br />
<br />
Another explanation for the constant buzzer is the High-frequency Doppler method for ionosphere research <sup>[11]</sup> described in the Russian Journal of Earth Sciences, in which radio waves are reflected from ionosphere inhomogeneities. Changes of an ionosphere state can be caused by solar geophysical or seismic events. This method involves comparing a continuous radio transmission which is reflected by the ionosphere with a stable basic generator. The continuously transmitted carrier frequency currently used for this research matches that of the Russian Buzzer (4.625&nbsp;MHz).<br />
<br />
==Other frequencies==<br />
A broadcast matching the primary 4625 kHz USB signal was heard on 6998 kHz USB in October 2015.<br />
<br />
==See also==<br />
* [[Russian Woodpecker]]<br />
* [[Dead Hand System]]<br />
<br />
==References==<br />
# [http://www.cvni.net/radio/e2k/e2k008/e2k08odd.html Oddities], ''[[ENIGMA2000|ENIGMA 2000]] Newsletter'' Issue 8, January 2002. <br />
# [http://www.radioscanner.ru/forum/index.php?action=vthread&topic=12415&forum=3&page=2 Военная жужжалка на 4625 кГц], 2004.<br />
# [[Ary Boender]]: [http://www.cvni.net/radio/nsnl/nsnl000/nsnl0a.html Numbers & oddities, Issue 1], ''[[World Utility News]]'', 1995.<br />
# Brian Rogers: [http://www.brogers.dsl.pipex.com/page5.html The Buzzer], ''Mystery Signals Of The Short Wave'', 2008.<br />
# [http://uk3-pn.mixstream.net/8026.m3u Livestream as of June 2010]<br />
# [http://www.youtube.com/watch?v=9mH77Wu0_eY Youtube recording of the Morse Code]<br />
# [http://web.archive.org/web/20071125051007/http://dxworld.com/markers.html Single letter markers – posts from the SPOOKS and WUN listservers] (http://dxworld.com/markers.html), 2000.<br />
# [http://mikeandsniffy.co.uk/thesecretsiteofmike/mikes.htm Mike and Sniffy's radio 'X' files]<br />
# [http://www.faqs.org/faqs/radio/phonetic-alph/full/ Phonetic alphabets], by the Internet FAQ Consortium<br />
# [http://archive.hard-core-dx.com/channels/rusdx/2004-12/20041212044623734.html RUS-DX # 137-B], ''[[Hard-Core-DX]] Mail List Archive'', December 12, 2004.<br />
# [http://elpub.wdcb.ru/journals/rjes/v10/2007ES000227/2.shtml High-frequency Doppler method for ionosphere research], ''Russian Journal of Earth Sciences, '''10''', 2008.<br />
<br />
<br />
* Location: 56<sup>0</sup> 4' 58" N - 37<sup>0</sup> 5' 22" E<br />
<br />
==External links==<br />
*[http://www.astrosol.ch/numberstations/index.html Number Stations] - Includes discussion of UVB-76.<br />
* NPR's [http://www.npr.org/templates/topics/topic.php?topicId=1074 Lost and Found Sound], 2000-05-26: [http://www.npr.org/programs/lnfsound/stories/000526.stories.html The Shortwave Numbers Mystery]<br />
*[http://sites.google.com/site/stationuvb76 UVB-76 Station Info] - All the information about UVB-76 by Years.<br />
*[http://qrg.broker.freenet6.net/details.php?id=19667 UVB76] at the [http://qrg.broker.freenet6.net/ Global Frequency Database]<br />
*[http://www.uvb-76.net UVB-76 Temporary Internet Relay] - Live Internet Streaming site, 900km NW from station.<br />
* Allison McLellan: "Decoding Numbers Stations", QST, '''103''' (11), pp. 70-74, ISSN 0033-4812, November 2019<br />
<br />
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{{CC-BY-SA-WP|UVB-76}}<br />
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[[Category:UVB-76|!]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Spy_Numbers_StationsSpy Numbers Stations2019-10-05T18:13:26Z<p>SV1XV: /* Further reading */ QST article</p>
<hr />
<div>'''Spy Numbers Stations''' are shortwave radio stations that are speculated to have been broadcasting since World War I. The true origin and purpose of them are unknown. A popular theory is that these stations are intended for spies in the field using a One Time Pad. Another theory is that they are used in drug smuggling operations.<br />
<br />
[[Image:Numbers stations map.gif|center|A map showing several locations of Number Stations]]<br />
<br />
<br />
== Description and operation ==<br />
<br />
Number stations are shortwave transmissions from foreign intelligence agencies to spies in the field of foreign countries. Since the fact of operating a number station is technically a state secret, there have been very few confirmations from government organizations - those that have were the Czech Office for Foreign Relations and Information (we also obtained a Top Secret document), Polish Institute of National Remembrance and the Swedish Security Service SÄPO. Usage of number stations has additionally been confirmed by former Cold War spies, and the cases of Kim Hyon-hui (1987), Erwin van Haarlem (1988), The Cuban Five (1998) and Andreas and Heindrun Anschlag (2011).<br />
<br />
Number stations transmit encrypted messages in forms of groups of numbers, or less commonly letters, using either automated voice (many languages), Morse code or digital signals. While the encryption method used for most number stations is unknown, some have used and others are widely believed to use one-time pad - mathematical addition of a set of random numbers (the key) to the plaintext, which can be used only once, and must be destroyed after usage. Some of the stations are believed to transmit pre-defined codebook instructions.<br />
<br />
Number stations offer a powerful advantage in our modern world: practically complete anonymity. The recipient of the message can be almost anywhere in the world, and receive instructions without fear of being traced through a phone call or internet connection. All the recipient needs is a shortwave radio and to be in the right place at the right time.<br />
<br />
The first account of a number station, as reported in ENIGMA Newsletter Issue #12, was from the Austrian Kurzwelle Panorama magazine dating from World War I. The BBC were noted for sending messages to people overseas which where coded messages to SOE agents during WW2. From then on encrypted messages broadcasted with creepy automated voices have been being sent with stations appearing and disappearing as political events changed over the last 60 years. The amount of active stations has significantly decreased since the late 1990s, though number stations are still actively used by countries such as Russia, Poland and Cuba.<br />
<br />
<br />
== ENIGMA naming system ==<br />
<br />
The most popular number station naming system was devised by the European Numbers Information Gathering and Monitoring Assocation (ENIGMA), a number station research group active in 1993-2000, and later maintained by ENIGMA 2000. It was created to solve ambiguities in number station reporting, and classifies stations by language or type of signal. Each ENIGMA designator consists of an alphabetic prefix followed by an ordinary number.<br />
<br />
Current prefixes:<br />
<br />
E - English language voice broadcasts<br />
<br />
G - German language voice broadcasts<br />
<br />
S - Slavic language voice broadcasts<br />
<br />
V - Voice broadcasts in all other languages<br />
<br />
M - Morse code<br />
<br />
F - Frequency-shift keying digital modes<br />
<br />
P - Phase-shift keying digital modes<br />
<br />
XP - Russian 7 digital modes<br />
<br />
HM - Hybrids of analog and digital modes<br />
<br />
<br />
== Active Spy Numbers Stations ==<br />
*[[V2]] Attencion Cuba<br />
*[[HM01]] Cuba<br />
*[[S06]] Russian Man, Russia<br />
*[[V13]] New Star Radio Taiwan<br />
*[[V24]] South Korea<br />
*[[V26]] China<br />
*[[M94]] South Korea<br />
*[[X06]] Mazielka, Russia<br />
*[[XUP]] Pulser, N. America<br />
*[[G2 (Swedish Rhapsody)]] Poland<br />
<br />
== Inactive Spy Numbers Stations ==<br />
*[[E10]] [[MOSSAD]] Israel<br />
*[[E3]] [[Lincolnshire Poacher]] Malta<br />
*[[M25]] KKN family, USA and worldwide<br />
*[[G03 (The Gong Station)]] East Germany<br />
<br />
== Parody Spy Numbers Stations ==<br />
[[Image:LadySpy.png|right|120px]]<br />
*[[Attention 69 Numbers Station]]<br />
*[[Brother Stair Numbers]]<br />
*[[Roman Numerals Numbers Station]]<br />
*[[WBNY]]<br />
<br />
== Unknown/anonymous spy number station ==<br />
*[[XM Whales (The Backwards Music Station)]]<br />
<br />
== See also ==<br />
* [[Cuban Intelligence Radio Stations/Operations]]<br />
* [[Soviet/Russian Strategic Communication/Warfare Units]]<br />
* [[The Russian Man (RU6)|The Russian Man]]<br />
* [[DGI]]<br />
* [[Havana Moon]]<br />
* [[Pedro]]<br />
* [[ENIGMA]]<br />
* [[ENIGMA2000]]<br />
* [[Langley Pierce]]<br />
* [[Numbers stations in popular culture]]<br />
<br />
==External links==<br />
*[http://en.wikipedia.org/wiki/Number_stations Numbers Station (Wikipedia)]<br />
*[http://en.wikipedia.org/wiki/The_Conet_Project The Conet Project (Wikipedia)]<br />
*[http://irdial.hyperreal.org/ Conet Project downloads]<br />
*[http://www.spynumbers.com Spy Numbers]<br />
* [http://www.simonmason.karoo.net/page30.html Simon Mason's website]<br />
<br />
==Further reading==<br />
* Langley Pierce: "Intercepting Numbers Stations", Interproducts, Perth, UK, ISBN 0-9519783-4-9, 1994.<br />
* Havana Moon: "[http://wrgpmusic.no-ip.org.nyud.net/UnoDosCuatro.pdf Uno, Dos, Cuatro - A Guide to the Numbers Stations]", Tiare Publications, Lake Geneva, ISBN 0-936653-06-X, 1987<br />
* Simon Mason: [http://www.simonmason.karoo.net/SECRET_SIGNALS.doc Secret Signals] (The Euronumbers Mystery), Tiare Publications, ISBN 0-936653-28-0.<br />
* Harry L. Helms, W5HLH: "How To Tune The Secret Shortwave Spectrum", TAB Books, ISBN 0-8306-1185-1, 1981.<br />
* Don Schimmel: "The Underground Frequency Guide", HighText, ISBN 1-878707-17-5, 1994<br />
* Allison McLellan: "Decoding Numbers Stations", QST, '''103''' (11), pp. 70-74, ISSN 0033-4812, November 2019<br />
<br />
[[Category:Radio station lists]]<br />
[[Category:Spy stations|!]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-06-11T02:16:30Z<p>SV1XV: /* Beacon lists */</p>
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<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons, with the exception of beacons participating to the Synchronized Beacon Project, in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU/NCDXF HF Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
===IARU 50 MHz Synchronized Beacon Project (SBP)===<br />
IARU promotes a network of synchronized beacons worldwide at the lower part of the 50 MHz (6m) band. Each IARU region is allocated a 10 kHz segment, which is divided into ten 1 kHz wide beacon channels. <br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region <br />
! Beacon frequencies (kHz)<br />
|-<br />
| align="center" | '''R1'''<br />
| 50000, 50001, 50002, 50003, 50004, 50005, 50006, 50007, 50008, 50009<br />
|-<br />
| align="center" | '''R2'''<br />
| 50010, 50011, 50012, 50013, 50014, 50015, 50016, 50017, 50018, 50019<br />
|-<br />
| align="center" | '''R3'''<br />
| 50020, 50021, 50022, 50023, 50024, 50025, 50026, 50027, 50028, 50029<br />
|-<br />
|}<br />
<br />
Each frequency can accomodate up to five beacons, which transmit sequentially in time slots (TS) 0 to 4. The transmission mode and sequence for each beacon is "PI4 - CW ID - carrier", lasting exactly one minute. SBP beacons transmit with 25W on a omnidirectional antenna. Currently a few coordinated beacons exist in IARU Region 1, in two clusters:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Frequency (kHz) <br />
! TS0 !! TS1 !! TS2 !!TS3 !! TS4<br />
|-<br />
| align="center" | '''50005'''<br />
| EI0SIX || GB3MCB || PI7SIX || GB3MCB || OZ4BHM<br />
|-<br />
| align="center" | '''50006'''<br />
| IW9GDC/B || IW9GDC/B || GB3NGI || IW9GDC/B || GB3NGI<br />
|-<br />
|}<br />
<br />
For more info, refer to: [https://www.rudius.net/oz2m/sbp/ Synchronized Beacon Project] by OZ2M.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Dennis, ZS4BS, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Dennis Green, ZS4BS: [https://iaruhfbeacons.wordpress.com/hf-beacons/ Worldwide List of HF Beacons].<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-06-11T02:15:48Z<p>SV1XV: /* Beacon lists */ ZS4BS replaces G3USF</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons, with the exception of beacons participating to the Synchronized Beacon Project, in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU/NCDXF HF Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
===IARU 50 MHz Synchronized Beacon Project (SBP)===<br />
IARU promotes a network of synchronized beacons worldwide at the lower part of the 50 MHz (6m) band. Each IARU region is allocated a 10 kHz segment, which is divided into ten 1 kHz wide beacon channels. <br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region <br />
! Beacon frequencies (kHz)<br />
|-<br />
| align="center" | '''R1'''<br />
| 50000, 50001, 50002, 50003, 50004, 50005, 50006, 50007, 50008, 50009<br />
|-<br />
| align="center" | '''R2'''<br />
| 50010, 50011, 50012, 50013, 50014, 50015, 50016, 50017, 50018, 50019<br />
|-<br />
| align="center" | '''R3'''<br />
| 50020, 50021, 50022, 50023, 50024, 50025, 50026, 50027, 50028, 50029<br />
|-<br />
|}<br />
<br />
Each frequency can accomodate up to five beacons, which transmit sequentially in time slots (TS) 0 to 4. The transmission mode and sequence for each beacon is "PI4 - CW ID - carrier", lasting exactly one minute. SBP beacons transmit with 25W on a omnidirectional antenna. Currently a few coordinated beacons exist in IARU Region 1, in two clusters:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Frequency (kHz) <br />
! TS0 !! TS1 !! TS2 !!TS3 !! TS4<br />
|-<br />
| align="center" | '''50005'''<br />
| EI0SIX || GB3MCB || PI7SIX || GB3MCB || OZ4BHM<br />
|-<br />
| align="center" | '''50006'''<br />
| IW9GDC/B || IW9GDC/B || GB3NGI || IW9GDC/B || GB3NGI<br />
|-<br />
|}<br />
<br />
For more info, refer to: [https://www.rudius.net/oz2m/sbp/ Synchronized Beacon Project] by OZ2M.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Dennis Green, ZS4BS: [https://iaruhfbeacons.wordpress.com/hf-beacons/ Worldwide List of HF Beacons].<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-04-07T12:21:08Z<p>SV1XV: /* Solitary beacons and channel markers */ W</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| '''3227.0''', 3335.0, '''3657.0''', 4028.0, '''4031''', 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, '''5466.0''', <br>6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0, 8895.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
* [[Fishnet_beacon|Fishing Net/Driftnet Beacons]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-03-11T06:52:33Z<p>SV1XV: /* 6 meters (50 MHz) beacons */</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons, with the exception of beacons participating to the Synchronized Beacon Project, in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU/NCDXF HF Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
===IARU 50 MHz Synchronized Beacon Project (SBP)===<br />
IARU promotes a network of synchronized beacons worldwide at the lower part of the 50 MHz (6m) band. Each IARU region is allocated a 10 kHz segment, which is divided into ten 1 kHz wide beacon channels. <br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region <br />
! Beacon frequencies (kHz)<br />
|-<br />
| align="center" | '''R1'''<br />
| 50000, 50001, 50002, 50003, 50004, 50005, 50006, 50007, 50008, 50009<br />
|-<br />
| align="center" | '''R2'''<br />
| 50010, 50011, 50012, 50013, 50014, 50015, 50016, 50017, 50018, 50019<br />
|-<br />
| align="center" | '''R3'''<br />
| 50020, 50021, 50022, 50023, 50024, 50025, 50026, 50027, 50028, 50029<br />
|-<br />
|}<br />
<br />
Each frequency can accomodate up to five beacons, which transmit sequentially in time slots (TS) 0 to 4. The transmission mode and sequence for each beacon is "PI4 - CW ID - carrier", lasting exactly one minute. SBP beacons transmit with 25W on a omnidirectional antenna. Currently a few coordinated beacons exist in IARU Region 1, in two clusters:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Frequency (kHz) <br />
! TS0 !! TS1 !! TS2 !!TS3 !! TS4<br />
|-<br />
| align="center" | '''50005'''<br />
| EI0SIX || GB3MCB || PI7SIX || GB3MCB || OZ4BHM<br />
|-<br />
| align="center" | '''50006'''<br />
| IW9GDC/B || IW9GDC/B || GB3NGI || IW9GDC/B || GB3NGI<br />
|-<br />
|}<br />
<br />
For more info, refer to: [https://www.rudius.net/oz2m/sbp/ Synchronized Beacon Project] by OZ2M.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/28.htm Worldwide List of HF Beacons] (temporarily inactive, [https://sv1xv.blogspot.com/p/g3usfs-worldwide-list-of-hf-beacons.html Last published version, May 23, 2018]).<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-03-11T06:50:08Z<p>SV1XV: /* IARU 50 MHz Synchronized Beacon Project (SBP) */ new section</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU/NCDXF HF Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
===IARU 50 MHz Synchronized Beacon Project (SBP)===<br />
IARU promotes a network of synchronized beacons worldwide at the lower part of the 50 MHz (6m) band. Each IARU region is allocated a 10 kHz segment, which is divided into ten 1 kHz wide beacon channels. <br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region <br />
! Beacon frequencies (kHz)<br />
|-<br />
| align="center" | '''R1'''<br />
| 50000, 50001, 50002, 50003, 50004, 50005, 50006, 50007, 50008, 50009<br />
|-<br />
| align="center" | '''R2'''<br />
| 50010, 50011, 50012, 50013, 50014, 50015, 50016, 50017, 50018, 50019<br />
|-<br />
| align="center" | '''R3'''<br />
| 50020, 50021, 50022, 50023, 50024, 50025, 50026, 50027, 50028, 50029<br />
|-<br />
|}<br />
<br />
Each frequency can accomodate up to five beacons, which transmit sequentially in time slots (TS) 0 to 4. The transmission mode and sequence for each beacon is "PI4 - CW ID - carrier", lasting exactly one minute. SBP beacons transmit with 25W on a omnidirectional antenna. Currently a few coordinated beacons exist in IARU Region 1, in two clusters:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Frequency (kHz) <br />
! TS0 !! TS1 !! TS2 !!TS3 !! TS4<br />
|-<br />
| align="center" | '''50005'''<br />
| EI0SIX || GB3MCB || PI7SIX || GB3MCB || OZ4BHM<br />
|-<br />
| align="center" | '''50006'''<br />
| IW9GDC/B || IW9GDC/B || GB3NGI || IW9GDC/B || GB3NGI<br />
|-<br />
|}<br />
<br />
For more info, refer to: [https://www.rudius.net/oz2m/sbp/ Synchronized Beacon Project] by OZ2M.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/28.htm Worldwide List of HF Beacons] (temporarily inactive, [https://sv1xv.blogspot.com/p/g3usfs-worldwide-list-of-hf-beacons.html Last published version, May 23, 2018]).<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-03-11T06:30:46Z<p>SV1XV: /* IARU/NDXF HF Beacon Project */</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU/NCDXF HF Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/28.htm Worldwide List of HF Beacons] (temporarily inactive, [https://sv1xv.blogspot.com/p/g3usfs-worldwide-list-of-hf-beacons.html Last published version, May 23, 2018]).<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-03-11T06:30:31Z<p>SV1XV: /* IARU Beacon Project */</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU/NDXF HF Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/28.htm Worldwide List of HF Beacons] (temporarily inactive, [https://sv1xv.blogspot.com/p/g3usfs-worldwide-list-of-hf-beacons.html Last published version, May 23, 2018]).<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
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<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-03-11T06:22:59Z<p>SV1XV: /* Beacon lists */ G3USF</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/28.htm Worldwide List of HF Beacons] (temporarily inactive, [https://sv1xv.blogspot.com/p/g3usfs-worldwide-list-of-hf-beacons.html Last published version, May 23, 2018]).<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-03-11T06:14:36Z<p>SV1XV: /* Further reading */ G4TMV guide</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.2 kHz || JN39dr || Radioamateurs du Luxembourg [http://www.rlx.lu/de/qso/repeaters/beacons.html]<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on [[11_meter|25545 kHz (25.545 MHz)]] and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/28.htm Worldwide List of HF Beacons] (temporarily inactive).<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012.<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-03-11T06:12:33Z<p>SV1XV: /* Further reading */ G4TMV guide</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| '''3227.0''', 3335.0, '''3657.0''', 4028.0, '''4031''', 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, '''5466.0''', <br>6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
# Alan Gale, G4TMV: "[https://www.ndblist.info/beacons/beacons.pdf An introduction to beacon DXing]", Version 1.0, December 2012, pp. 36-38.<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-03-11T05:48:15Z<p>SV1XV: /* Solitary beacons and channel markers */ V on 4031.0, 5466.0</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| '''3227.0''', 3335.0, '''3657.0''', 4028.0, '''4031''', 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, '''5466.0''', <br>6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Radio_propagation_beaconRadio propagation beacon2019-02-19T17:22:42Z<p>SV1XV: /* Beacon lists */ HF list currently inactive</p>
<hr />
<div>[[Image:DK0WCY-station.jpg|thumb|right|DK0WCY & DRA5 beacons]]<br />
A '''radio propagation beacon''' is a [[radio beacon]], which is mainly used for investigating the propagation of radio signals. Currently most radio propagation beacons use [[amateur radio]] frequencies.<sup>(26)</sup> They can be found on HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.<sup>[1]</sup> <sup>[2]</sup> Andy Talbot, G4JNT, gives the following definition for beacons licensed in the Amateur Radio service: ''A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes''.<sup>[1]</sup><br />
<br />
==History==<br />
The earliest record of radio propagation beacons goes back to World War II, when the German military operated propagation beacons on wavelengths of approximate 80 m and 10 m. Many propagation beacons were installed during the International Geophysical Year 1957-1958 These included amateur radio beacons OZ7IGY and GB3IGY (later GB3RAL) on 144 MHz, which are still operational, as well as the now defunct DM3IGY in East Germany on 28001 kHz. <sup>(19)</sup> GB3IGY transmitted with the unusual for the time high power of 1 kW. It was situated at Badgers Mount, Sevenoaks, England and was operated by Ken Ellis, G5KW.<sup>(22)</sup><br />
<br />
==Transmission characteristics==<br />
[[File:WB0RIO-CW-beacon.jpg|thumb|right|A CW beacon keyer based on discrete CMOS digital chips.]]<br />
The majority of propagation beacons operate in continuous wave (CW or A1A) and transmit their identification (callsign and location) in Morse code. Some of them send long dashes (sometimes at varying power levels) to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like [[RTTY|radioteletype]] (F1B) and [[PSK31]] (G1B).<br />
<br />
Most beacons consist of a simple digital keyer, based on discrete digital electronics or a microcontroller, and a low power transmitter or tranceiver. FT-897, a budget HF tranceiver produced by Yaesu/Vertex, has a programmable beacon mode and is used in some temporary propagation beacon installations. Recently K6HX published a versatile Morse code keyer design based on the popular Arduino microcontroller platform.<br />
<br />
Antennas usually are types with low directivity. There are exceptions, however, like the high power beacons with directional antennas, specifially set up for transatlantic VHF propagation experiments.<br />
<br />
==160 meters beacons==<br />
<br />
The IARU Region 2 (North and South America) bandplan reserves the range 1999&nbsp;kHz to 2000&nbsp;kHz for propagation beacons.<br />
<br />
==60 meters beacons==<br />
<br />
In addition to the DARC and RSBG beacon projects on [[Fixed/Mobile_bands|5195 and 5290 kHz]] (see below), Eddie Bellerby of [[UDXF]] discovered in March 2011 a new CW beacon on 5206 kHz, sending LX0HF, presumably from Luxembourg.<sup>[13]</sup> Further intelligence indicates that the beacon is operated by Philippe LX2A/LX7I of the Luxembourg Amateur Radio Society.<sup>[14]</sup> Two more european beacons are listed on 5 MHz, OV1BCN on 5290 kHz, operated by OZ1FJB and OK1IF on 5258.5 kHz from the Czech Republic, though their current status is unclear.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DRA5 || 5195.0 kHz || JO44VQ || DARC<br />
|-<br />
| LX0HF || 5205.3 kHz || ||<br />
|-<br />
| HG7BHB || 5252.3 kHz || JN97LE || <br />
|-<br />
| OK1IF || 5258.5 kHz || JO40HG || Inactive. Recording: [http://ok1if.c-a-v.com/5MHzOK/OK4AS.WAV]<br />
|-<br />
| GB3RAL || 5290.0 kHz || IO91IN || RSGB, inactive <br />
|-<br />
| GB3WES || 5290.0 kHz || IO84QN || RSGB, inactive<br />
|-<br />
| GB3ORK || 5290.0 kHz || IO89JA || RSGB, inactive<br />
|-<br />
| OV1BCN || 5290.5 kHz || JO55SI || Op OZ1FJB [http://www.oz1fjb.dk/page8.html]<br />
|-<br />
| HB9AW || 5291.0 kHz || JN47BE || [https://www.hb9aw.ch/bake-5000khz/] <br />
|-<br />
| SZ1SV || 5398.5 kHz || KM17UX || Op SV1IW & SV1JG. Inactive.<br />
|-<br />
|}<br />
<br />
==30 meters beacons==<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Frequency !! Locator !! Details<br />
|-<br />
| DK0WCY || 10144.0 kHz || JO44VQ || DARC<br />
|-<br />
| IK3NWX || 10137.3 kHz || JN55VF || nr Monselice, PD 15m asl<br />
|-<br />
|}<br />
<br />
==10 meters beacons==<br />
[[File:K5DZE BCN QSL.jpg|thumb|right|QSL card from K5DZE 28 MHz beacon at Dry Ridge, KY.]]<br />
Most HF radio propagation beacons are found in the 10 meters (28&nbsp;MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28&nbsp;MHz frequencies are allocated to radio propagation beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! IARU Region<br />
! Beacon allocations<br />
|-<br />
| R1<br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 WW Time Shared<br />
* 28201-28225 Continuous Duty<br />
|-<br />
| R2<sup>[3]</sup><br />
|<br />
* 28190-28199 Regional Time Shared<br />
* 28199-28201 IBP/NCDXF<br />
* 28201-28225 Beacons, continuous duty<br />
* 28225-28300 Shared<br />
|-<br />
| R3<br />
|<br />
* 28190-28200 IBP<br />
|-<br />
|}<br />
<br />
==40 MHz beacons==<br />
* The first radio propagation beacon on 40 MHz is OZ7IGY in Jystrup, Denmark (JO55WM) and transmits on 40071&nbsp;kHz <s>40021 kHz</s>. Transmitted power is 20 W to a dipole antenna. <!-- Modulation is F1A keying (frequency Shift Keying), with a shift of 250 Hz. [http://www.oz7igy.dk/] --> The beacon is frequency- and time-locked to GPS. The sequence is programmed to send PI4 , followed by a short pause, and then the call sign and grid locator sent in CW, then a pause, and a carrier until start of the next cycle. PI4 is a digital mode specifically designed for beacons and propagation studies, similar to JT4 and WSPR. To decode PI4, tune 800 Hz below the nominal frequency.<br />
* The [[Radio Society of Great Britain]] has a license for beacon transmissions from GB3RAL (Didcot, UK) on 40050 & 60050&nbsp;kHz.<br />
<br />
==6 meters (50 MHz) beacons==<br />
[[Image:LX0FOUR antenna.jpg|thumb|right|Antenna tower of LX0SIX and LX0FOUR beacons]]<br />
In the 6 meters (50&nbsp;MHz) band, beacons traditionally operate in the lower part of the band, in the range 50000&nbsp;kHz to 50080&nbsp;kHz. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50&nbsp;MHz openings.<br />
<br />
The ARRL bandplan recommends 50060 to 50080&nbsp;kHz for beacons in the United States. <br />
<br />
In Australia beacons operate from 50280 to 50350&nbsp;kHz.<br />
<br />
The new IARU Region 1 bandplan moves 50&nbsp;MHz beacons in a new allocation, 50400 to 50500&nbsp;kHz.<br />
<br />
==4 meters (70 MHz) beacons==<br />
<br />
===General beacon operations===<br />
Numerous beacons operate on 70 MHz in recent years. Their main purrpose is to dected the relativley rare and extreme Es (sporadic E) opennings, which exceed 70 MHz.<br />
<br />
There is no definite international beacon allocation, due to various countries having different [[amateur radio]] allocations in this band. Generally beacons operate near the bottom end (70.000-70.100 MHz).<sup>(11) (12)</sup>. Most respect the [[RSGB]] bandplan, staying below 70.050 MHz.<br />
<br />
* 70.000-70.050 MHz: UK beacon allocation, including personal beacons on 70.030 MHz<br />
<br />
===Special beacon allocations===<br />
* USA: 70.005 MHz is allocated to the WE9XFT beacon. Transmits from Bedford, VA, under an FCC experimental license issued to Brian Justin, WA1ZMS, with a power of 3 kW. In 2012 this beacon shall transmit from the same location under new callsign WF9XRU.<br />
* Austria: 70.045 MHz is allocated to the OE5QL beacon.<br />
* Hong Kong: 71.757 MHz is allocated to the VR2FOUR beacon.<br />
<br />
==VHF/UHF beacons==<br />
[[Image:GB3VHF-rack.jpg|thumb|right|GB3VHF propagation beacon (144 MHz)]]<br />
Beacons on 144&nbsp;MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different ITU/IARU regions and countries. <br />
<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" | IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 2&nbsp;m<br />
| align="center" | 144.400-144.490<br />
| align="center" | 144.275–144.300<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 1.25&nbsp;m<br />
| align="center" | N/A<br />
| align="center" | 222.050–222.060<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 70&nbsp;cm<br />
| align="center" | 432.800-432.990<br />
| align="center" | 432.300–432.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 33&nbsp;cm<br />
| align="center" | N/A<br />
| align="center" | Varies Locally<br />
| align="center" | N/A<br />
|-<br />
| align="center" | 23&nbsp;cm<br />
| align="center" | 1,296.800-1,296.990<br />
| align="center" | 1,296.070-1,296.080<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 13&nbsp;cm<br />
| align="center" | 2,320.800-2,320.990<br />
| align="center" | 2,304.300-2,304.400<br />
| align="center" | Unknown<br />
|-<br />
|}<br />
<br />
The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:<sup>[4]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Band<br />
! Beacon allocation (kHz)<br />
|-<br />
| 4 m<br />
| 70,000-70,030<br />
|-<br />
| 2 m<br />
| 144,400-144,490<br />
|-<br />
| 70&nbsp;cm<br />
| 432,800-432,990<br />
|-<br />
| 23&nbsp;cm<br />
| 1296,800-1296,990<br />
|-<br />
|}<br />
<br />
===ON0EME moon beacon===<br />
[[File:ON0EME capture.jpg|thumb|right|Screen capture of ON0EME by G4DZU]]<br />
A beacon specifically for earth-moon-earth (EME or "moonbounce") reception became operational in 2012 in Belgium. The beacon uses call sign ON0EME and transmits on 1296.0 MHz with a very high power of 1000 kW ERP. The antenna is a solid parabolic reflector with a diameter of 3.7 m. <sup>[17]</sup><br />
<br />
===144 MHz transatlantic beacons===<br />
<br />
A number of VHF beacons have been installed on both shores of the Atlantic Ocean, as an early warning system for exceptional sporadic-E (Es) conditions, which shall allow transatlantic QSOs on 2 m. The followng list includes most beacons, not all of them are always operational.<sup>[23]</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Callsign !! Locator !! Frequency (kHz) !! Info<br />
|-<br />
| CU2VHF || HM77DT || 144401 || <br />
|-<br />
| CU8DUB || HM49KL || 144420 || <br />
|-<br />
| D4C/B || HK76MV || 144436 || 750 m ASL, 20W CW. Copied by Dave Pedersen, PJ4VHF/N7BHC, on Bonaire Island on May 6, 2015 [http://www.arrl.org/news/cape-verde-2-meter-beacon-heard-in-bonaire]<br />
|-<br />
| ED8ZAA/B || IL18 || 144484 ||<br />
|-<br />
| GB3WGI<sup>[24]</sup> || IO64BL || 144487 || 100 W CW and JT65. Activated on June 4, 2013. <br />
|-<br />
| K4MHZ || FM25 || 144300 || 2M Transatlantic Beacon, Hatteras, NC: CW at 10 WPM. Running 100W to a 12 element long Yagi at 50' on a center azimuth of 70 degrees towards the Azores, Canary Islands, and southern Europe/North Africa. <br />
|-<br />
| N7BHC || FM15PA || 144291 || Mode: CW, 13 WPM. Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA (15 second carrier) (15 seconds receive period). Location: 35.0302 N - 76.7146 W <br />
|-<br />
| NP2X/B || FK77PR || 144291 || St. Croix, US Virgin Islands - 240 feet AMSL (73 meters AMSL) - RF Concepts 160 watt, reduced to 100 watts for beacon operation - 15 element yagi @ beam heading of 55 degrees (Portgual) - np2xbeacon@gmail.com <br />
|-<br />
| PY2MTV/B || GG66va || 144300 || Beaming to AF/EU<br />
|-<br />
| VE1SMU/H || || 144.288 ||<br />
|-<br />
| VO1ZA || GN37JS || 144400 || Inactive<br />
|-<br />
| W1RJA/B || FN41CJ || 144282 || Southern Rhode Island. Emission: A1 (amplitude keyed CW) Power: 60 Watts Feedline: 160' Cablewave FLC 12-50 half inch hardline. Antenna: 9.5 dBd 5 element yagi beaming 60 degrees azimuth. Height: 140 feet (43M) above base elevation of 130 feet (40M) ASL<br />
|-<br />
| WA1ZMS || FM07FM || 144285 || Activated on October 29, 2006 - 4200FT AMSL - Antenna: 2-yagi pair, Directive Systems DPM144-5 Antenna gain: 11.5dBd Radiated power: 1400W ERPd)<br />
|-<br />
|}<br />
<br />
===Indian Ocean beacon project===<br />
<br />
An Australian ham radio group has set up a beacon to investigate if there is any VHF ducting between Australia and South Africa. Beacon VK6RIO is located in Perth, W. Australia and operates on 144.950 MHz. The beacon transmits 100 watts into four 8-element Yagis with digital Chirp modulation. This special modulation scheme can be detected some 50 dB below the noise floor.<br />
<br />
The beacon is GPS locked both in frequency, time and Chirp synchronisation. In order to detect the Chirp beacon, the receiving station requires a GPS locked [[Software Defined Radio]] (SDR), a GPS locked 144 MHz down-converter and 1 PPS signal from a GPS receiver to time stamp received signals. Open source PC software by Hermann, DL3HVH, shall be made available for processing the received signals.<br />
<br />
==SHF and microwave beacons==<br />
<br />
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3 cm (10 GHz) band are unusual.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! rowspan="2" | Band<br />
! colspan="3" | Beacon Sub-band (MHz)<br />
|- style="background: #E7E7FF"<br />
! align="center" |IARU R1<br />
! align="center" |IARU R2<br />
! align="center" |IARU R3<br />
|-<br />
| align="center" | 9&nbsp;cm<br />
| align="center" | 3,400.800-3,400.995<br />
| align="center" | 3,456.300-3,456.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 5&nbsp;cm<br />
| align="center" | 5,760.800-5,760.995<br />
| align="center" | 5,760.300-5,760.400<br />
| align="center" | Unknown<br />
|-<br />
| align="center" | 3&nbsp;cm<br />
| align="center" | 10,368.800-10,368.995<br />
| align="center" | 10,368.300-10,368.400<br />
| align="center" | Unknown <sup>(25)</sup><br />
|-<br />
| align="center" | 1.2&nbsp;cm<br />
| align="center" | 24,048.800-24,048.995<br />
| align="center" colspan="2"| Beacons are rare<br />
|}<br />
<br />
==Optical and infrared beacons==<br />
Recently some groups of [[amateur radio|radio amateurs]], especially in Great Britain, experiment with two-way communications on optical wavelengths. This activity has led to the design and installation of a few beacons operating on optical wavelengths. These beacons transmit modulated light using high intensity LEDs and are used mainly for equipment setting and calibration. An interesting example is the optical beacon located at GB3CAM (Wyton, UK) operating at 628 nm.<sup>[16]</sup><br />
<br />
==License-free experimental beacons==<br />
<br />
Main articles: ''[[LowFER]]'', ''[[HiFER]]''.<br />
<br />
These are extremely low power experimental beacons which operate legally without a license on specific bands, which are reserved for very short range radio transmissions or for industrial, scientific and medical devices (ISM) and in which a limited level of radiated RF energy is allowed. They are operated as radio propagation experiments by radio amateurs and other radio hobbyists.<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! Type !! Frequencies !! Countries !! [[FCC]] Part 15 rules<br />
|-<br />
| [[LowFER]] || 160-190&nbsp;kHz || USA, Canada || § 15.217<br />
|-<br />
| MedFER || 510 & 1704 kHz<BR>(510-1705 kHz) || USA, Canada || § 15.219 <br />
|-<br />
| BeFER || 6776 kHz || Canada || - <br />
|-<br />
| [[HiFER]] || 13553-13567 kHz || USA, Canada || § 15.225<br />
|-<br />
| 49ers || 49846 kHz<BR>(49820-49900 kHz) || USA || § 15.235 <br />
|-<br />
|}<br />
<br />
==Beacon projects==<br />
[[File:TS-50S NCDXF beacon.png|thumb|right|NCDXF-IARU beacon setup]]<br />
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the [[International Telecommunications Union]] and the International Amateur Radio Union.<br />
<br />
===IARU Beacon Project===<br />
[[Image:IARU.gif|left|50px|url="http://www.darc.de"]]<br />
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation (NCDXF) and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100&nbsp;kHz, 18110&nbsp;kHz, 21150&nbsp;kHz, 24930&nbsp;kHz, and 28200&nbsp;kHz. <sup>[5]</sup> The IARU/NDXF beacons transmit in turns on the five designated frequencies according to the following schedule, which repeats every 3 minutes:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF" <br />
! Slot !! DXCC entity !! Call !! Location !! Latitude !! Longitude !! Grid Sq !! 14100 !! 18110 !! 21150 !! 24930 !! 28200 !! Operator<br />
|- <br />
| 01 || United Nations || 4U1UN || New York City || 40º 45' N || 73º 58' W || FN3ØAS || 00.00 || 00.10 || 00.20 || 00.30 || 00.40 || UNRC<br />
|-<br />
| 02 || Canada || VE8AT ||Eureka, Nunavut || 79º 59' N || 85º 57' W || EQ79AX || 00.10 || 00.20 || 00.30 || 00.40 || 00.50 || RAC<br />
|-<br />
| 03 || United States || W6WX || Mt. Umunhum || 37º 09' N || 121º 54' W || CM97BD || 00:20 || 00.30 || 00:40 || 00.50 || 01:00 || NCDXF<br />
|-<br />
| 04 || Hawaii || KH6WO || Laie || 21º 38' N || 157º 55' W || BL11AP || 00.30 || 00.40 || 00.50 || 01.00 || 01.10 || (Off)<br />
|-<br />
| 05 || New Zealand || ZL6B || Masterton || 41º 03' S || 175º 36' E || RE78TW || 00.40 || 00.50 || 01.00 || 01.10 || 01.20 || NZART<br />
|-<br />
| 06 || Australia || VK6RBP || Rolystone || 32º 06' S || 116º 03' E || OF87AV || 00.50 || 01.00 || 01.10 || 01.20 || 01.30 || WIA<br />
|-<br />
| 07 || Japan || JA2IGY || Mt. Asama || 34º 27' N || 136º 47' E || PM84JK || 01.00 || 01.10 || 01.20 || 01.30 || 01.40 || JARL<br />
|-<br />
| 08 || Russia || RR9O || Novosibirsk || 54º 59' N || 82º 54' E || NO14KX || 01.10 || 01.20 || 01.30 || 01.40 || 01.50 || SRR<br />
|-<br />
| 09 || Hong Kong || VR2B || Hong Kong || 22º 16' N || 114º 09' E || OL72BG || 01.20 || 01.30 || 01.40 || 01.50 || 02.00 || HARTS<br />
|-<br />
| 10 || Sri Lanka || 4S7B || Colombo || 6º 6' N || 80º 13' E || NJ06CC || 01.30 || 01.40 || 01.50 || 02.00 || 02.10 || RSSL<br />
|-<br />
| 11 || South Africa || ZS6DN || Pretoria || 25º 54' S || 28º 16' E || KG44DC || 01:40 || 01.50 || 02:00 || 02:10 || 02:20 || ZS6DN<br />
|-<br />
| 12 || Kenya || 5Z4B || Kariobangi || 1º 15' S || 36º 53' E || KI88KS || 01.50 || 02.00 || 02.10 || 02.20 || 02.30 || ARSC<br />
|-<br />
| 13 || Israel || 4X6TU || Tel Aviv || 32º 03' N || 34º 46' E || KM72JB || 02:00 || 02:10 || 02:20 || 02.30 || 02:40 || IARC<br />
|-<br />
| 14 || Finland || OH2B || Lohja || 60º 19' N || 24º 50' E || KP2Ø || 02:10 || 02:20 || 02:30 || 02:40 || 02:50 || SRAL<br />
|-<br />
| 15 || Madeira || CS3B || Santo da Serra || 32º 43' N || 16º 48' W || IM12OR || 02.20 || 02.30 || 02.40 || 02.50 || 00.00 || ARRM <br />
|-<br />
| 16 || Argentina || LU4AA || Buenos Aires || 34º 37' S || 58º 21' W || GFØ5TJ || 02:30 || 02:40 || 02:50 || 00.00 || 00:10 || ARC<br />
|-<br />
| 17 || Peru || OA4B || Lima || 12º 04' S || 76º 57' W || FH17MW || 02.40 || 02.50 || 00.00 || 00.10 || 00.20 || RCP<br />
|-<br />
| 18 || Venezuela || YV5B || Caracas || 10º 25' N || 66º 51' W || FK6ØNJ || 02:50 || 00.00 || 00:10 || 00:20 || 00:30 || RCV<br />
|-<br />
|}<br />
<br />
The original NCDXF/IARU beacon project, coordinated by John W6ISQ, consisted of nine 100W beacons which operated only on 14100 kHz on a coordinated 10 minute sequence. The beacons used to send a longer callup sequence, like "QST DE 4U1UN/B BEACON" followed by dashes with 100 W, 10 W, 1 W, and 100 mW, finally ending with "4U1UN/B SK". The original beacons were 4U1UN/B, W6WX/B, KH6O/B, JA2IGY, 4X6TU, OH2B, CT3B, ZS6DN and LU4AA. This network evolved into its current format with 18 beacons on five frequencies around 1999.<sup>(15)</sup> The current beacons consist of a Kenwood TS-50 tranceiver, a beacon controller, a vertical antenna and a GPS unit.<br />
{{Clear}}<br />
<br />
===ITU sponsored beacons===<br />
<br />
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, 59.6042<sup>0</sup>N - 5.29167<sup>0</sup>E) and at Darwin, Australia (callsign VL8IPS, 12.6042<sup>0</sup>S - 131.2920<sup>0</sup>E). The beacons operated on frequencies 5471.5&nbsp;kHz, 7871.5&nbsp;kHz, 10408.5&nbsp;kHz, 14396.5&nbsp;kHz, and 20948.5&nbsp;kHz.<sup>(6)</sup> <sup>(15)</sup> <sup>(27)</sup> Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed. <sup>(7)</sup> <sup>(20)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center" style="background: #F3F3FF"<br />
|- <br />
| '''HF Field-Strength measurement campaign'''<br />
<br />
For a number of years, ITU-R Study Group 3 has been promoting a world-wide HF field-strength measurement campaign, the impetus for which arose from WARC HFBC-87 and the request for improved accuracy in HF propagation prediction. At that time, the Study Group recognised that significant improvements in HF propagation prediction methods needed a substantial body of new measurement data and to that end, administrations and organisations were invited to participate in the measurement campaign, either by installing suitable transmitters or by collecting long-term data from appropriate receiving systems. The campaign is specified in Recommendation ITU-R P.845 'HF field-strength measurement' and comprises a world-wide network of transmitters and receivers using coded transmissions on pre-determined frequencies.<br />
<br />
The reasons for the campaign and the continuing need for participation in it, are underlined in Resolution ITU-R 27 (HF field-strength measurement campaign). So far, regular transmissions are being provided by the Administrations of Australia and Norway. Details of the transmitter in Norway, operated by the Norwegian Telecommunications Authority and Telenor Broadcasting, are given below: <br />
<br />
|- <br />
| '''Radio Beacon LN2A'''<br />
<br />
[[File:QSL LN2A front.jpg|right|200px]]<br />
[[File:QSL LN2A back.jpg|right|200px]]<br />
* Identification signal (Morse code): LN2A <br />
* Location: Sveio, Norway 59 deg 37 min N, 5 deg 19 min E <br />
* Hours of transmission: 24 hours per day <br />
* Assigned frequencies: 5471.225 kHz, 7871.225 kHz, 10408.225 kHz, 14396.225 kHz and 20946.225 kHz<br />
* Reference frequencies, corresponding to suppressed carrier frequencies when using suppressed carrier SSB techniques: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: ICOM IC 725 transceiver, IC-4KL PA <br />
* Transmitted power: approximately 1 kW on all frequencies <br />
* Antenna: 5 band trap vertical monopole <br />
* Mode: Suppressed carrier SSB, with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above the reference frequency, and the FSK "space" 1650 Hz above the reference frequency. <br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule: <br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 14395 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 20945 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 5470 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 7870 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 10407 || align="center" | 16 - 36 - 56<br />
|}<br />
<br />
Administrations and organizations participating in the work of ITU-R are invited to consider the possibility of participating in the campaign, either through the provision of transmissions or by the collection of field strength measurement data, both in accordance with the specifications given in Recommendation ITU-R P.845. For further details on the campaign, including the availability of a suitable receiving system, please contact the ITU-R Counsellor for Study Group 3 (Dr. Kevin A. Hughes) at ITU Headquarters, in Geneva.<br />
<br />
The Norwegian Telecommunications Authority and Telenor Broadcasting would be pleased to acknowledge reception reports of LN2A with a QSL card.<br />
<br />
The contact address is:<br />
<br />
Norwegian Telecommunications Authority (Att. AYO/TF)<BR><br />
P O Box 447 Sentrum<BR><br />
N-0104 Oslo <BR><br />
Norway <BR><br />
<br />
|- <br />
| '''Radio Beacon VL8IPS'''<br />
<br />
This beacon was established by IPS Radio and Space Services in conjuction with thw Royal Australian Navy.<br />
* Identification signal (in Morse code): VL8IPS<br />
* Location: Humpty Doo, near Darwin, Northen Territory, 12 deg 36 min S - 131 deg 16 min 51 sec E<br />
* Hours of transmission: 24 hours per day<br />
* Assigned frequencies: 5470 kHz, 7870 kHz, 10407 kHz, 14395 kHz and 20945 kHz<br />
* Transmitter: Rockwell Collins HF-8022<br />
* Transmitter power: approximately 2 kW on all frequencies<br />
* Antenna: AEA 628D biconical monopole<br />
* Mode: suppressed carrier SSB (USB & LSB) with the reference frequencies (suppressed carrier frequencies) 1225 Hz below the assigned frequencies, with the FSK "mark" 800 Hz above reference frequency and the FSK "space" 1650 Hz above the reference frequency.<br />
* Signal duration and format: as specified in Recommendation ITU-R P.845; 4 min for each frequency, 20 min for all five frequencies according to the following schedule:<br />
<br />
{| style="background: #F3FFF3"<br />
! Reference frequency (kHz) !! Minutes after each hour<br />
|-<br />
| align="center" | 5470 || align="center" | 00 - 20 - 40 <br />
|-<br />
| align="center" | 7870 || align="center" | 04 - 24 - 44 <br />
|-<br />
| align="center" | 10407 || align="center" | 08 - 28 - 48 <br />
|-<br />
| align="center" | 14395 || align="center" | 12 - 32 - 52 <br />
|-<br />
| align="center" | 20945 || align="center" | 16 - 36 - 56<br />
|-<br />
|}<br />
<br />
* Reception reports could be sent beacon@ips.gov.au<br />
|-<br />
|}<br />
<br />
===DARC beacon project===<br />
[[Image:DARC.png|left|50px]]<br />
[[Image:DRA5-QSL.jpg|right|200px]]<br />
The [[Deutscher Amateur Radio Club]] (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel (54.6875<sup>0</sup>N - 9.79167<sup>0</sup>E, JO44VQ). <sup>[8]</sup> These beacons are DRA5 on 5195&nbsp;kHz and DK0WCY on 10144&nbsp;kHz. In addition to identification and location, every 10 minutes these beacons transmit solar, geomagnetic and ionospheric bulletins. Transmissions are in Morse code (CW) for aural reception, [[RTTY]] (45 baud 170 Hz at HH+10) and [[PSK31]] (at HH+50). <sup>[9]</sup> DK0WCY operates also a limited service beacon on 3579&nbsp;kHz at 0720-0900 and 1600-1900 local time.<br />
<br />
{{Clear}}<br />
<br />
===RSGB 5 MHz beacon project===<br />
[[Image:RSGB-Logo.png|left|50px]]<br />
The [[Radio Society of Great Britain]] (RSGB) operates three radio propagation beacons on 5290&nbsp;kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot (51.5625<sup>0</sup>N - 1.29167<sup>0</sup>W, IO91IN), GB3WES in Cumbria (54.5625<sup>0</sup>N - 2.625<sup>0</sup>W, IO84QN) and GB3ORK in the Orkney Islands (59.0208<sup>0</sup>N - 3.20833<sup>0</sup>W, IO89JA). <br />
<br />
Beacon GB3RAL, which is located at the Rutherford-Appleton Laboratory (RAL), also transmits continuously on 28215&nbsp;kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053&nbsp;kHz).<sup>[10]</sup> <br />
<br />
As of August 2017 the 5 MHz beacon at Didcot is not operational. The other two beacons are active. In addition to Morse code, beacon GB3ORK also transmits in JT9 on the minute following its regular transmission.<br />
<br />
=== U.S. Navy beacons ===<br />
A radio propagation beacon with callsign NAF was installed in 1983 at Cape Prince, Wales, AK. It transmitted both CW and FSK identification with 100 W to a three-band fan dipole on 5604, 11004 and 16804 kHz. The project, which included reception sites at Fairbanks, AK, Seattle, WA, State College, PA and San Diego, CA, was coordinated by the U.S. Naval Security Group Command and its purpose was to verify and calibrate HF propagation prediction software. <sup>(15)</sup> It is not known when the project was terminated.<br />
<br />
Another propagation beacon was installed in 1991 at the Arctic Submarine Laboratory at Cape Prince of Wales, AK. The beacon operated on 25545 kHz and tranmitted the morse code letter "R". A reception facility existed at Fairbanks, AK, some 900 km away. The R beacon was used to study aurora and sporadic E events at high geographical latitudes.<sup>(18)</sup><br />
<br />
===WSPR Network===<br />
This is an a large scale [[amateur radio]] propagation beacon project which uses the WSPR (Weak Signal Propagation Reporter) transmission scheme available with the WSJT software suite, created by Joe Taylor, K1JT. The loosely-coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The [http://wsprnet.org/drupal/ WSPRnet website] provides detailed propagation report databases and real-time graphical maps of propagation paths. WSPR Network operates on the following amateur radio frequencies (USB dial settings in kHz) 136.0, 502.4, 1836.6, 3592.6, 5287.2, 7038.6, 101387.0, 14095.6, 18104.6, 21094.6, 24924.6, 28124.6, 50293.0, 70028.6 and 144489.0 kHz.<br />
<br />
==The future of radio propagation beacons==<br />
<br />
It seems that there is no longer an interest in HF radio propagation by international organizations, government departments or research institutes, therefore they shall be operated only as part of the [[amateur radio]] service.<br />
<br />
A slow process is underway to supplement morse code (CW) identification, which is mostly suitable for aural reception, with digital modulation patterns. The RSGB beacons on 5290 kHz already transmit such code for 30" in each transmission. In the 2011 [[Radio Society of Great Britain|RSGB]] Convention, Bo OZ2M shall talk about the introduction of ''machine generated modulation'' to most radio propagation beacons, in order to enable automatic monitoring.<br />
<br />
Beacon timing functions are also modernized. When more beacons share a frequency, they are synchronized by electronic clocks locked to GPS satellite transmissions.<br />
<br />
==See also==<br />
* [[Ionosonde]]<br />
* [[Radio beacon]]<br />
* [[JG2XA]]: AN HF Doppler investigation beacon project.<br />
* [[Letter beacon]]<br />
* [[High Frequency Beacon]]<br />
* [[Part_15_Beacons]]<br />
<br />
==Notes and references==<br />
[[Image:QSL-N7LT-BCN.jpg|thumb|right|QSL card from beacon N7LT/BCN on 28248.5 kHz]]<br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(5), pp.56-58 (May 2008). <br />
# Andy Talbot, G4JNT: "Amateur Beacons", ''[[Radio User]]'', ISSN 1748-8117, '''3'''(8), pp. 30-33 (August 2008)<br />
# [http://www.iaru-r2.org/wp-content/uploads/region-2-mf-hf-bandplan-e.pdf New IARU Region 2 bandplan introduced in January 2008]<br />
# [http://www.qsl.net/g3yrc/Bandplans/UK%20VHF.htm Amateur Radio UK VHF Bandplan], Great Yarmouth Radio Club<br />
# [http://www.ncdxf.org/pages/beacons.html International Beacon Project] by the Northern California DX Foundation (2008)<br />
# [http://www.ham-radio.nl/bakenshf/baken0-20mhz.htm HF 0-20 MHz beacons]<br />
# [http://www.itu.int/dms_pub/itu-r/opb/res/R-RES-R.27-1993-PDF-E.pdf ITU Resolution ITU-R 27/1993: HF Field-strength measurement campaign] (PDF) <br />
# [http://www.dk0wcy.de/ Aurora beacon DKØWCY] by Deutscher Amateur-Radio-Club e.V. ([[DARC]]), 2004.<br />
# Pat Hawker, G3VA: "The DK0WCY/DRA5 Propagation Beacons", ''Technical Topics Scrapbook - All 50 years'', [[Radio Society of Great Britain]], ISBN 9781-9050-8639-9, pp. 98 (2008)<br />
# Mike Willis, G0MJW: "The GB3RAL VHF Beacon cluster", ''RadCom'', '''84'''(04), [[Radio Society of Great Britain]], pp. 65-59, April 2008.<br />
# The Four meters website: [http://www.70mhz.org/beacons.htm 70 MHz beacon list]<br />
# The Four meters website: [http://www.70mhz.org/bandplan_uk.htm RSGB 4m bandplan]<br />
# Southgate Amateur Radio Club: [http://www.southgatearc.org/news/march2011/lx0hf_beacon.htm Luxembourg 60m beacon LX0HF]<br />
# [http://www.radioamateurs-online.fr/2011/03/luxembourg-une-balise-sur-60m-lx0hf/ Luxembourg: Une balise sur 60m LX0HF] Radioamateurs-Online, March 11, 2011.<br />
# G. Jacobs, W3ASK, T.J. Cohen, N4XX and R.B. Rose, K6GKU: "The New Shortwave Propagation Handbook", ''CQ Communications, Inc.'', New York, ISBN 0-945016-11-8, pp. 5-17, 5-18. (1995).<br />
# Stuart Wisher, G8CYW: "More adventures in optical communications", ''RadCom'', '''88'''(05), [[Radio Society of Great Britain]], pp. 41, May 2012<br />
# Joe Lynch, N6CL: "VHF Plus", ''CQ Amateur Radio", '''88'''(07), pp. 81, July 2012.<br />
# Rose, R., Hunsucker, R.D. and Lott G.K.: "Results from a year-long Auroral-E measurement campaign", ''Naval Command, Control and Ocean Surveillance Center'', San Diego, CA, April 1993.<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 1", ''RadCom'', '''89'''(02), [[Radio Society of Great Britain]], pp. 22, February 2013.<br />
# IPS Radio and Space Services: [http://www.ips.gov.au/beacon/vl8ips.html Radio Beacon VL8IPS] (dead link)<br />
# Martin Harrison, G3USF: "Getting started in... beacons, part 2", ''RadCom'', '''89'''(03), [[Radio Society of Great Britain]], pp. 30, March 2013.<br />
# Charlie Newton, G2FKZ: "Radio Auroras", revised edition edited by Steve Telenius-Lowe, 9M6DXX, [[Radio Society of Great Britain]], ISBN 9781-9050-8681-8, pp. 8, 2012.<br />
# [http://www.g4cqm.co.uk/beacons.html 144 MHz Transatlantic Beacon List] by Derek Hilleard G4CQM<br />
# "GB3WGI 144 MHz transatlantic beacon", ''RadCom'', '''89'''(08), [[Radio Society of Great Britain]], pp. 11, August 2013.<br />
# Allocations vary by country. In Australia, VK3RMB is on 10368.536 MHz, VK3RGI on 10368.434 MHz and VK3RXX on 10368.530 MHz.<br />
# According to USA/FCC rules, a Beacon is defined as ''an amateur station transmitting communications for the purposes of observation of propagation and reception or other related experimental activities.'' (Part 79.3.a.9) <br />
# "[https://drive.google.com/file/d/0B5wD1M7AJBTEc0dyUEQtXzVfYjA/view?usp=sharing HF Propagation Beacons]", ''Shortwave Magazine'' , '''59''' (5), ISSN 0037-4261, pp.37, May 2001.<br />
<br />
==Beacon lists==<br />
<br />
Currently there is one regularly updated international beacon list, compiled by Martin, G3USF, and is available on-line. An additional online list by WJ5O contains only 28 MHz (10 meter) beacons.<br />
<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/28.htm Worldwide List of HF Beacons] (temporarily inactive).<br />
* Martin Harrison, G3USF: [http://www.keele.ac.uk/depts/por/50.htm Worldwide List of 50 Beacons].<br />
* William H Hays, WJ5O: [http://userpages.troycable.net/~wj5o/bcn.htm Ten meter propagation beacons]<br />
<br />
==Further reading==<br />
[[Image:IK0WRB-beacon10.png|thumb|right|IK0WRB beacon keyer schematic]]<br />
* [http://www.ncdxf.org/beacons.html IARU/NDXF International Beacon Project]<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 1", QST, The American Radio Relay League, October 1994, pp. 31-33.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Part 2", QST, The American Radio Relay League, November 1994, pp. 49-51.<br />
* John G. Troster, W6ISQ, & Robert S. Fabry, N6EK: "The NCDXF/IARU International Beacon Network - Report and Update", QST, The American Radio Relay League, September 1997, pp. 47-48.<br />
* Ken Reitz, KS4ZR: "[http://www.monitoringtimes.com/MT-10meters.pdf Exploring the World of 10 Meter Beacons]", ''[[Monitoring Times]]'', May 2007, pages 14-16.<br />
* R.Wilkinson, G6GVI, S.Cooper, GM4AFF, & B. Hansen, OZ2M: "[http://www.70mhz.org/beacons.htm The 70 MHz Beacon List]", ''The Four Metres Website'', 2008.<br />
* John Jaminet, W3HMS and Charlie Heisler, K3VDB: "Building a beacon for 2401 MHz", ''CQ VHF'', '''10'''(3), CQ Communications, Inc, ISSN 1085-0708, pages 44–46, 2007.<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/5MHzBcnsWeb.pdf Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK].<br />
* Andrew Talbot, G4JNT: [http://www.g4jnt.com/BeaconPres-2.ppt The Next Generation of Beacons for the 21st century] (PPT format).<br />
* UK Microwave Group (UKMuG): [http://www.microwavers.org/indexb.htm UK Amateur Radio & Microwave Beacons].<br />
* [http://www.g0afh.com/gb3vhf/index.html GB3VHF – a beacon designed for the 21st Century]<br />
* [http://web.tiscalinet.it/vcoletti/pic/keyer/beacon.html IK0WRB beacon keyer], based on a PIC16F84 microcontroller.<br />
* [http://www.dk0wcy.de/ Aurora Beacon DK0WCY]<br />
* [http://www.oz1fjb.dk/page_1269782382686.html OV1BCN]: a new HF propagation beacon on 5290.5 kHz. <br />
* [http://users.telenet.be/BEACONCLUSTER/home.html BEACONCLUSTER] worldwide beacon maps by Richard Kaminski ON4CJU.<br />
* [http://brainwagon.org/2009/11/14/another-try-at-an-arduino-based-morse-beacon/ K6HX beacon keyer] using an [http://www.arduino.cc Arduino] microcontroller board.<br />
* [http://www.solorb.com/elect/hamcirc/beacon/index.html WB0RIO Morse Code Beacon Keyer]: a beacon keyer based on CMOS digital componets, by G. Forrest-Cook, WB0RIO (1996).<br />
* [http://www.ac6v.com/beacons.htm Beacons a Bunch]: software resources for monitoring IARU/NCDXF beacons, compliled by Jeff Dinkins, AC6V.<br />
* [http://www.earf.co.uk/light_beacon.htm Low power 628nm (red) light beacon], co-sited with GB3CAM beacons at Wyton<br />
* [http://www.on0eme.org ON0EME moon beacon status]<br />
<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|-<br />
| '''FCC rules, §97.203 Beacon station.'''<br />
<br />
* (a) Any amateur station licensed to a holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, Technician Plus, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held.<br />
<br />
* (b) A beacon must not concurrently transmit on more than 1 channel in the same amateur service frequency band, from the same station location.<br />
<br />
* (c) The transmitter power of a beacon must not exceed 100 W.<br />
<br />
* (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands.<br />
<br />
* (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944.<br />
<br />
** (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.<br />
<br />
** (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate.<br />
<br />
* (f)A beacon must cease transmissions upon notification by a District Director that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the District Director.<br />
<br />
* (g) A beacon may transmit one-way communications.<br />
|-<br />
|}<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=aF8zc8zRaok 10 Meter Amateur Radio Propagation CW Beacon Demo] by KI7F (Youtube video).<br />
# [http://www.youtube.com/watch?v=8dyDte9kSkU 10 Meter beacon equipment]: Modified CB radio using a freakin` beacon controller (Youtube video).<br />
# [http://www.youtube.com/watch?v=Uy3ufVTsqKE Arduino Morse Beacon Keyer] by Mark VandeWettering K6HX (Youtube video).<br />
<br />
<br />
{{CC-BY-SA-WP|Amateur_radio_propagation_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Tom_KneitelTom Kneitel2019-02-03T20:05:50Z<p>SV1XV: /* External links */ ARRL orbituary</p>
<hr />
<div>[[Image:Tom K2AES.jpg|right]]<br />
Tom Kneitel, W4XAA, K2AES, SK (1933-2008)<br />
<br />
As a teenager growing up in New York City, Tommy operated an AM pirate station known as [[WISP]]. During a DX test in 1949, he received reception reports as far away as Ohio. Later he became the first, and only, journalist to visit Swan Island and Radio Americas, and his article about the journey appeared in the July, 1968 issue of Electronics Illustrated. According to Art, N2AH, Tom actually operated an [[amateur radio]] station from Swan Island as KS4CH. The article hit newsstands at almost exactly the same time Radio Americas left the air!<br />
<br />
Kneitel was Editor of [[Popular Communications]] from its launch in 1982 until 1995, when he gave up day-to-day responsibilities for the magazine and became Senior Editor. He served as an advisor and resource to his successors until recently before his passing. In addition to innumerable articles in Popular Communications, he also published numerous radio and DX related articles in "Popular Electronics", "S9" and "CB Horizons". Occasionally he used the pen name "[[Alice Brannigan]]".<br />
<br />
He also owned the small publishing house CRB Research Books, Inc, in Commack, NY, which published most of his books in the 1980s and 1990s.<br />
<br />
Kneitel was inducted into the [[CQ Amateur Radio Hall of Fame]] in 2004.<br />
<br />
{{Clear}}<br />
<br />
==Books by Tom Kneitel==<br />
[[Image:K2AES-QSL.png|thumb|right|QSL card of Tom Kneitel, K2AES, showing his former callsigns, including KS4CH used from Swan Island.]]<br />
Kneitel had authored a multitude of books on [[DXing]], CB, scanning and other radio-related topics, most of them published by CRB Research Books, Inc, in Commack, NY. This is an incomplete list of his books:<br />
<br />
* Electronic circuits handbook (1963)<br />
* Tom Kneitel & Robert M. Mendelson: "103 simple transistor projects", Hayden Book Co, ISBN 0810-40952-1 (1964)<br />
* Surplus conversion handbook, including "command sets" (1967)<br />
* Robert M. Brown & Tom Kneitel: "49 Easy Entertainment & Sience Projects", Howard W. Sams & Co., Inc (1969)<br />
* Tom Kneitel: "CBers' SSB handbook", Hayden Book Co, ISBN 0810-40857-9 (1977)<br />
* The "top secret" registry of U.S. Government radio frequencies, 25 to 470 MHZ (1979-1986)<br />
* Air-scan directory of aero band scanner frequencies (1981)<br />
* Tom Kneitel & Robert M. Brown: "101 Easy Test Instrument Projects", TAB Books, ISBN 0-830613397 (1981)<br />
* Tom Kneitel: "Rail-scan Directory of railroad scanner frequencies", CRB Research, ISBN 0-939780-12-7 (1982)<br />
* National directory of survival radio frequencies (1982)<br />
* Tom Kneitel: "Air Scan Guide to Aeronautical Communications" (4th ed), CRB Research, ISBN 0-939780-03-8 (1984)<br />
* Radio station treasury, 1900-1946 (1986)<br />
* Tom Kneitel: "Guide to embassy & espionage communications", CRB Research, ISBN 0939780062 (1986)<br />
* Tune in on Telephone Calls (1988)<br />
* Tomcat's Big CB Handbook (1988)<br />
* Tom Kneitel: "Directory of U. S. Army Forts, Camps, and Airfields 1789 to 1945", CRB Research, ISBN 093978016X (1992)<br />
<br />
==Monitor Registration Program==<br />
[[Image:WPE6AF.png|thumb|right|WPE registration certificate for WPE6AF]]<br />
[[Image:Monitor Station Registry Application.jpg|thumb|right|Application form for the CRB Monitor Station Registry]]<br />
Tom Kneitel run the [[WPE Monitor Registration Program]] of [[Popular Electronics]] during the late 1950s until 1961.<sup>(1)</sup> <br />
<br />
Later, after the cancellation of the WPE registration service run by [[Hank Bennet]]<sup>(3)</sup>, Kneitel launched a similar program through his company CRB Research as the '''Monitor Station Registry'''.<sup>(2)</sup> The CRB registration scheme also issued callsign-like identifiers, following the tradition of WR0, WPE and WDX schemes. Prefixes started with letter "K", followed by two letters indicating the State and a digit according to the [[amateur radio]] US prefix areas, so a DXer in New York would have an identifier starting with KNY2 while a DXer in California one starting with KCA6.<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
| '''Tom Kneitel on the WPE monitor registration program:'''<br />
Here's a little background on the program's early days.[http://www.qsl.net/wb1gfh/swl.html]<br />
<br />
Originally, during the mid-1950's, a DX'er named Joe P. Morris was issuing SWL ID's with a WR0 prefix. For an SASE, you got a mimeographed strip with only an ID, which was written in by hand. As time went on, Roberts decided it required more time and effort than he had available. He was asking around if anyone was interested in taking it over. I volunteered. At that time I was writing for Popular Electronics, and asked Perry Ferrell, the editor, if they would like to sponsor the project as a service to readers. They agreed and said they would publicize it as a Popular Electronics program, print up the certificates, etc. I was put in charge of the project and my signature was printed on the certificates. We also decided to reorganize the project and replace the WR0 with WPE. The original run of certificates had pre-printed ID's running from WPE1AA through WPE0ZZ.<br />
<br />
I believe they announced the project late in the 1950's and the response was overwhelming. I processed the applications and typed in the names and dates. It didn't take long for me to run through all of the certificates. The next batch of certificates (to cover ID's with 3-letter suffixes) did not have pre-printed ID's. We did not keep records as to the specific ID assignments. I typed in the ID's, names, dates on those certificates. I handled this program until the spring of 1961 when I became the editor of another radio magazine. At that time, Popular Electronics redesigned the WPE certificate, removed my signature, and replaced it with those of [[Oliver P. Ferrell|Perry Ferrell]] and of Hank Bennett, the DX editor of Popular Electronics. I don't know much about the program after that but I know it existed for a number of years. I believe the WDX program came later and was run by a radio club and did not have any any connection with either WPE or Popular Electronics.<br />
<br />
Hope that's of interest and use.<br />
<br />
73,<br />
<br />
Tom Kneitel, K2AES/ WPE2AB<br />
|-<br />
|}<br />
<br />
==Notes and references==<br />
# In April 1961 Kneitel left Popular Electronics to become Editor of Horizons Publications (CB/DX'ing Horizons Magazine).<br />
# Jerome S. Berg: "Listening on the short waves, 1945 to today", McFarland, ISBN 0786439963, page 361, 2008.<br />
# After leaving Popular Electronics, Bennet took over the WPE program using his own resources, as the [[WDX registration service]], which, according to John Herkimer, was still active in 2000.<br />
<br />
==External links==<br />
* John Herkimer: "[http://pl703.pairlitesite.com/WPE.html The "WPE" Monitor Registration Program]"<br />
* ARRL: "[http://www.arrl.org/news/prolific-author-tom-kneitel-w4xaa-sk Prolific Author Tom Kneitel, W4XAA SK]" (2008-08-25)<br />
<br />
<br />
[[Category:People]]<br />
[[Category:DXing]]<br />
[[Category:Monitor registration schemes]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-02-03T19:48:26Z<p>SV1XV: /* Solitary beacons and channel markers */ V</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| '''3227.0''', 3335.0, '''3657.0''', 4028.0, 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-02-03T09:14:50Z<p>SV1XV: /* Cluster beacons */ 7039 -> 7509</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code. The cluster centered on 7509.0 kHz in the past transmitted on 7039.0 kHz, within the 40m international amateur radio allocation.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, 7509.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3335.0, '''3657.0''', 4028.0, 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-02-02T19:01:49Z<p>SV1XV: /* Solitary beacons and channel markers */ V</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, <S>7039 kHz,</S> 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, <s>7038.7,</s> 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, <s>7039.0,</s> 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, <s>7039.1,</s> 5709.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3227.0, 3335.0, '''3657.0''', 4028.0, 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-02-02T18:56:17Z<p>SV1XV: /* Solitary beacons and channel markers */ V</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, <S>7039 kHz,</S> 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, <s>7038.7,</s> 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, <s>7039.0,</s> 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, <s>7039.1,</s> 5709.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| '''3657.0''', <s>3658.0</s>, 4028.0, 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-01-20T15:23:59Z<p>SV1XV: /* Cluster beacons */ corr</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, <S>7039 kHz,</S> 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.8<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, <s>7038.7,</s> 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, <s>7039.0,</s> 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, <s>7039.1,</s> 5709.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3658.0, '''4028.0''', 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-01-20T15:20:22Z<p>SV1XV: /* Solitary beacons and channel markers */ bold</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, <S>7039 kHz,</S> 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.9<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, <s>7038.7,</s> 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, <s>7039.0,</s> 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, <s>7039.1,</s> 5709.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3658.0, '''4028.0''', 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, '''8497.8'''<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-01-13T20:01:53Z<p>SV1XV: /* Cluster beacons */</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, <S>7039 kHz,</S> 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.9<br />
|-<br />
| align="center" | '''D''' || '''RCV'''<br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, <s>7038.7,</s> 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || '''RIT'''<br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || '''RIW'''<br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, <s>7039.0,</s> 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, <s>7039.1,</s> 5709.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || '''RTS'''<br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3658.0, '''4028.0''', 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, 8497.8<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
<br />
[[Category:Beacons]]</div>SV1XVhttps://hfunderground.com/wiki/index.php/Letter_beaconLetter beacon2019-01-13T20:01:00Z<p>SV1XV: /* Location of letter beacons */</p>
<hr />
<div>[[Image:LetterBeacon-D-5153 7 kHz.png|thumb|right|250px|Letter Beacon D on 5153.7 kHz]]<br />
A '''Letter beacon''' (or '''single letter beacon''') is a high frequency (HF) radio transmission of uncertain origin, which consists of only a single repeating [[Morse Code]] letter.<br />
<br />
These transmissions sre often referred to as:<br />
* "Letter beacons"<br />
* SLB, or "Single Letter Beacons"<br />
* SLHFB, or "Single Letter High Frequency Beacons", the original [[SPEEDX]] designation.<br />
* SLHFM, or "Single Letter High Frequency Markers"<br />
* Cluster beacons<br />
* MX — an [[ENIGMA]] <sup>(1)</sup> and [[ENIGMA2000|ENIGMA-2000]] <sup>(2)</sup> designation.<br />
<br />
<br />
==History==<br />
<br />
The letter beacon radio transmissions were discovered in the late 1960s but were known only to a few specialized [[DXing|DXer]]s. Their presence became known to the wider [[amateur radio]] community in 1978, when beacon “W” started transmitting on 3584&nbsp;kHz, in the 80 meters band. [[SPEEDX]] published indirect evidence that this particular transmitter was located in Cuba. <sup>(3)</sup><br />
<br />
In 1982 [[SPEEDX]] reported, supposedly on the basis of HF direction finding by the US military, that beacon “K” transmitting on 9043&nbsp;kHz was located at 48° 30' N - 134° 58' E, near the city of Khabarovsk in the USSR. <sup>(4), (5)</sup> A few years later, W. Orr, W6SAI, suggested that the "K" beacons were actually located at Petropavlovsk on the Kamchatka Peninsula and the "U" beacons were located at the Barents Sea coast, between Murmansk and Amderma. <sup>(6)</sup><br />
<br />
==Location of letter beacons==<br />
<br />
According to Schimmel, in 1986 the [[FCC]] released the following HF direction finding results for single letter beacons, all of which indicate locations in the USSR: <sup>(5)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| C || Moscow, RUS<br />
|-<br />
| D || Odessa, UKR<br />
|-<br />
<br />
|-<br />
| O || Moscow, RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| S || Arkhangelsk, RUS<br />
|-<br />
| U || Between Murmansk & Amderma, RUS<br />
|-<br />
| Z || Mukachevo, UKR<br />
|-<br />
|}<br />
<br />
The link with the USSR and, more recently, Russia is further supported by the existence of single letter beacons transmitting letters existing only in the [[:Image:Rusian-CW.png|Cyrillic morse code alphabet]], like the '''Ю''' beacon <sup>(22)</sup> which operated on 13627 and 13639 kHz in the early 1980s. <br />
<br />
The '''[[ENIGMA]] group''' also accepted these locations for cluster beacons "C", "D", "P" and "S", adding Vladivostok for beacon "F". <sup>(7)</sup><br />
A recent source (2006) regarding locations was published on the Web by [[Ary Boender]].<sup>(8)</sup>&nbsp;<sup>(24)</sup> This publication also contains an extensive list of frequencies of letter beacons, both current and historical. The following locations are stated for cluster beacons:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter<br />
! Callsign<br />
! Location<br />
|-<br />
| A || || Astrakhan, RUS (tentative)<br />
|-<br />
| C || RIW || Moscow, RUS<br />
|-<br />
| D || RCV || Sevastopol, UKR<br />
|-<br />
| F || RJS || Vladivostok, RUS<br />
|-<br />
| K || RCC || Petropavlovsk-Kamchatsky, RUS<br />
|-<br />
| L || || Unknown, appeared on July 1, 2011<br />
|-<br />
| M || RTS || Magadan, RUS<br />
|-<br />
| P || RMP || Kaliningrad, RUS<br />
|-<br />
| S || RIT || Severomorsk, RUS<br />
|-<br />
|}<br />
<br />
For solitary beacons and markers, Boender suggests these locations:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Location<br />
|-<br />
| L || Tirana, ALB (defunct)<br />
|-<br />
| R || Izhevsk (Ustinov), RUS<br />
|-<br />
| P || Kaliningrad, RUS<br />
|-<br />
| V || Khiva, UZB <BR>or Almaty, KAZ <sup>(25)</sup><br />
|-<br />
|}<br />
<br />
Transmissions of the "P" beacon in December 2007, even on medium frequency (420 and 583&nbsp;kHz) indicate the Russian Naval Base of Kaliningrad as a possible source. <sup>(9)</sup> Kaliningrad officially uses the ITU registered callsign '''RMP'''. The identity of "P" beacon as an alias for RMP was first discovered by Ary Boender in 1995, when it transmitted RTTY weather forecast for Baltic Sea using callsign RMP on 3262 kHz [http://www.numbersoddities.nl/MX.pdf].<br />
<br />
==Types of letter beacons==<br />
The single letter beacons are currently classified in two groups, the "Cluster beacons" and the "Channel markers". A beacon "P" exists in both groups. A third group, the FSK beacons, is now extinct. The following sections list the beacons currently (July 2010) active, according to published listeners’ reports.<br />
<br />
===Cluster beacons===<br />
A group of radio beacons with single-letter identifiers ("C", "D", "M", "S", "P", "A", "M" and "K") have been regularly reported in small spectrum segments centered around 3594 kHz, 4558 kHz, 5154 kHz, <S>7039 kHz,</S> 7509 kHz, 8495 kHz, 10872 kHz, 13528 kHz, 16332 kHz and 20048 kHz. The term "cluster beacons" is frequently used for them, as these beacons transmit in parallel on frequencies only 0.1 kHz apart. These beacons transmit only their single-letter identifier in standard CW (A1A) using morse code.<br />
<br />
The following callsigns and frequencies of cluster beacons have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter !! Regular callsign !! Channel<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''L''' <sup>(21)</sup> ||<br />
| align="center" | -0.8<br />
| 5156.8, 7038.2, 7041.8<sup>(23)</sup>, 8494.2, 8497.9<br />
|-<br />
| align="center" | '''D''' || <br />
| align="center" | -0.3<br />
| 3593.7, 4557.7, 5153.7, <s>7038.7,</s> 7508.7, 8493.7, 10871.7, 13527.7, 16331.7, 20047.7<br />
|-<br />
| align="center" | '''P''' || '''RMP'''<br />
| align="center" | -0.2<br />
| 3593.8, 4557.8, 5153.8, 7038.8, 8494.8, 10871.8, 10872.8 <sup>(21)</sup>, 13527.8,<BR>16331.8, 20047.8<br />
|-<br />
| align="center" | '''S''' || <br />
| align="center" | -0.1<br />
| 3593.9, 4557.9, 5153.9, 7508.9, 8494.9, 10871.9, 13527.9, 16331.9, 20047.9<br />
|-<br />
| align="center" | '''C''' || <br />
| align="center" | 0.0<br />
| 3594.0, 4558.0, 5154.0, <s>7039.0,</s> 7509.0, 8495.0, 10872.0, 13528.0, 16332.0, 20048.0<br />
|-<br />
| align="center" | '''A''' ||<br />
| align="center" | +0.1<br />
| 3594.1, 4558.1, 5154.1, <s>7039.1,</s> 5709.1, 8495.1, 10872.1 13528.1 16332.1 <sup>(10)</sup><br />
|-<br />
| align="center" | '''F''' || '''RJS'''<br />
| align="center" | +0.2<br />
| 5156.8, 7039.2, 8495.2, 10872.2, 13528.2, 16332.2<br />
|-<br />
| align="center" | '''K''' || '''RCC'''<br />
| align="center" | +0.3<br />
| 4558.3, 5154.3, 7039.3, 8495.3, 10872.3, 16332.3<br />
|-<br />
| align="center" | '''M''' || <br />
| align="center" | +0.4<br />
| 5154.4, 7039.4, 8495.4, 10872.4, 13528.4, 16332.4 <br />
|-<br />
|}<br />
<br />
Occasionally some cluster beacons (especially "F" and "M") have been reported transmitting on frequencies different from their regular channel for short periods.<br />
<br />
===Solitary beacons and channel markers===<br />
A second family of letter beacons includes those operating outside the clusters. For this reason they are often called "Solitary beacons" or "Solitaires". These beacons also transmit their single-letter identifier in standard CW (A1A) using Morse code.<br />
<br />
A few solitary beacons, like "R" on 4325.9 kHz and 5465.9&nbsp;kHz, operate exactly like the cluster beacons, sending only their single letter identifier. <sup>(20)</sup> <br />
<br />
The majority of solitary beacons, and most notably "P" on various MF and HF frequencies, most of the time transmit their single-letter identifier in morse code. However, occasionally the routine transmission is interrupted and brief messages are sent in fast Morse code or in an FSK digital mode. Therefore, the proper term for these beacon-like single-letter transmissions is "channel markers" <sup>(6) (15)</sup>, as their purpose is to occupy and identify a particular HF transmission channel when no traffic is transmitted. There is no evidence that the cluster beacon "P" and the solitary beacon "P" are directly related. <br />
<br />
It was reported in Numbers and Oddities, issue 142, that beacon C on 8000 kHz also transmitted messages under the regular callsign '''RIW''', which is allocated to a Russian naval communications station in Khiva, Uzbekistan. <sup>(11)</sup><br />
<br />
There are also a few oddities, transmitting signals with poor modulation and irregular timing, like "V" on 5342 and 6430.7&nbsp;kHz.<br />
<br />
The following callsigns and frequencies of solitary beacons and markers have been reported recently in [http://www.ary.luna.nl Numbers&Oddities newsletter], [[Utility DX Forum]] and [[ENIGMA2000|ENIGMA-2000]]:<br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''R''' <sup>(20)</sup><br />
| align="center" |<br />
| 4325.9, 5465.9<br />
|-<br />
| align="center" | '''V'''<br />
| align="center" | <br />
| 3658.0, '''4028.0''', 4108.0<sup>(18)</sup>, 4150.0, '''5094.0''', 5141.0, 5342, 6430.7, 6498.0, 6809, 7027.5, 8103.5, 10202<br />
|-<br />
| align="center" | '''P''' <sup>(12)</sup><br />
| align="center" | '''RMP''' <br />
| 420, 448, 474, 490<sup>(17)</sup>, 583, <BR>3167, 3291, 3327, 3699.5, 3837, 4031, 4043, 4079<br />
|-<br />
| align="center" | '''C'''<br />
| align="center" | '''RIW'''<br />
| 8000<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7830.5<sup>(27)</sup><br />
|-<br />
| align="center" | '''L''' || || 6917.4, 8497.8<br />
|-<br />
| align="center" | '''W''' || || 8162.0 <br />
|-<br />
|}<br />
<br />
Channel marker "W", which appeared in 2012, is possibly related to a net for Russian Air Force Tu-95MS Bear H strategic bombers.<br />
<br />
===FSK beacons===<br />
This group included the "K" and "U" beacons, which are no longer active. They transmitted their morse code single letter identification by shifting the frequency of the carrier by approximately 1000 Hz. This mode of "FSK-CW" has the [[ITU]] designation '''F1A'''. The use of FSK indicated that the transmitter was suitable for FSK data transmissions, like [[RTTY]].<sup>(26)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ID letter <br />
! Regular callsign<br />
! Frequencies (kHz) <br />
|-<br />
| align="center" | '''K''' <br />
| align="center" |<br />
| 4005, 7906, 8144, 8158, 9043,<BR> 10571, 11555, 12150, 14477, 14967,<BR> 18348<br />
|-<br />
| align="center" | '''U'''<br />
| align="center" | <br />
| 7569, 9057, 10216, 12185, 12238, <BR>15655<br />
|-<br />
|}<br />
<br />
==ENIGMA designation==<br />
<br />
[[Chris Midgley]] and [[Mike Gaufman]] of [[ENIGMA]] devised a naming scheme for all stations in their sphere of interest. In the original scheme, the following identifications were issued to letter beacons: <sup>(13)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Cluster beacons<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” beacons, not in clusters<br />
|-<br />
| align="center" | '''MXS'''<br />
| Solitaires: letter beacons out of cluster bands<br />
|-<br />
| align="center" | '''MXF'''<br />
| FSK beacons (K, U), no longer active in 1995<br />
|-<br />
|}<br />
<br />
[[ENIGMA2000|ENIGMA-2000]], the internet based ENIGMA successor group, revised the original ENIGMA designators. The current designations for letter beacons are the following (since 2007):<sup>(14)</sup><br />
<br />
{| border="1" cellspacing="0" cellpadding="5" align="center"<br />
|- style="background: #E7E7FF"<br />
! ENIGMA ID <br />
! Description<br />
|-<br />
| align="center" | '''MX'''<br />
| Solitary HF single letter beacons<br />
|-<br />
| align="center" | '''MXI'''<br />
| Single letter beacons in clusters<br />
|-<br />
| align="center" | '''MXII'''<br />
| FSK beacons (K, U), no longer active<br />
|-<br />
| align="center" | '''MXV'''<br />
| Irregular “V” transmissions<br />
|-<br />
| align="center" | '''MXP'''<br />
| Letter beacons also sending messages<br />
|-<br />
| align="center" | '''MXIII'''<br />
| (deleted, merged with MX)<br />
|-<br />
| align="center" | '''MXIV'''<br />
| (deleted, merged with MX)<br />
|-<br />
|}<br />
<br />
==Purpose of letter beacons==<br />
The purpose and the applications of letter beacons are not yet known with certainty. Many theories and speculations have appeared in specialized bublications, but none is based on documentary evidence. They have been postulated to be [[radio propagation beacon]]s, channel markers, used in tracking satellites, or used for civil defense purposes. <sup>(15)</sup> Some stations of this family, in particular the “U” beacon, have been implicated in deliberate [[Radio jamming|jamming]]. <sup>(16)</sup><br />
<br />
Today the [[radio propagation beacon]] theory is generally accepted for the cluster beacons. According to ENIGMA the cluster beacons are used by the Russian Navy (and especially the submarine branch) to find the most suitable radio frequency for contact based on current radio propagation conditions. <sup>(7)</sup><br />
<br />
Connolly also links "P" channel marker with communications facilities at the Russian naval base of Kaliningrad. <sup>(9)</sup> "P" transmissions carrying Russian Navy "XXX" (flash priority) morse code messages with callsigns '''RPM''' and '''RDL''' further support this view.<br />
<br />
==Similar systems==<br />
[[Image:QSL-C-300.png|thumb|right|QSL card from a USCG beacon with signle letter ID]]<br />
A few aero navigation [[Radio beacon#Radio navigation beacons|Non Directional Beacons]] (NDBs) and marine beacons also transmit single letter identification codes. They can be easily distinguished from Letter beacons as they transmit in the allocated low frequency and medium frequency bands, most of them are listed in appropriate aviation handbooks and their transmission mode is A2A (full carrier with audio modulation).<br />
<br />
Some [[High Frequency Beacon]]s also transmit a single letter as identification. On September 7, 2010 a beacon was heard on 9111.7 kHz at 1546 UTC. It sent a slow marker "A", which did not sound like a Russian beacon (MX). It sounded like somebody was playing with the key sending letters "A" and "M". Transmission lasted untill at<br />
least 1630 UTC. <sup>(19)</sup><br />
<br />
==See also==<br />
* [[Spy Numbers Stations]]<br />
* [[High Frequency Beacon]]<br />
* [[ENIGMA]]<br />
* [[Radio propagation beacon]]<br />
<br />
==Notes & References==<br />
# ''[[ENIGMA]]'' stands for "European Numbers Information Gathering and Monitoring Association". It was a unique association of radio listeners based in the United Kingdom and operated during the 1990’s. <br />
# ''[[ENIGMA2000]]'' is an internet based community with the same general interests as the old ENIGMA association and with wider coverage of general Intelligence matters. This group produces a regular newsletter and maintains the old ENIGMA station naming scheme. ENIGMA-2000 shows less interest in letter beacons than its predecessor.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page K1.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, pages K7-K10.<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994, pages 78–83.<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'', ISSN 0733-3315, December 1984, pages 28-31.<br />
# "Station News", ENIGMA Newsletter, issue 18, January 2008, page 15.<br />
# Ary Boender: "Channel Markers & Cluster Beacons", http://www.numbersoddities.nl/MX-profile.pdf , September 2006. <br />
# Robert Connolly: "Maritime matters: Why we hear more signals from the Russian Navy?", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 3.1, January 2008, page 32.<br />
# Ary Boender: "Numbers & Oddities" issue 135, http://www.ary.luna.nl/2008.zip , December 2008.<br />
# Ary Boender: "Numbers & Oddities" issue 142, http://www.ary.luna.nl/no142.zip , July 2009.<br />
# Some transmission are in FSK morse code (F1A) instead of CW (A1A), but other beacon characteristics classify it as a solitary "P" beacon.<br />
# "Station Naming", ENIGMA Newsletter, issue 7, January 1995<br />
# ENIGMA Control List, Number 23, ENIGMA-2000, October 2007, http://www.ominous-valve.com/ecl23.pdf<br />
# Poundstone Willian: "Big Secrets", Quill, New York, 1983, ISBN 0688048307, pages 191-193<br />
# Pleikys Rimantas: Jamming, Rimantas Pleikys, Vilnius 1998<br />
# Robert Connolly: "DGPS, Single Letter Beacons and NDB changes", ''[[Radio User]]'', ISSN 1748-8117, PW Publishing Ltd, Issue 5.10, October 2010, page 49.<br />
# Ary Boender: "Numbers & Oddities" issue 159, http://www.numbersoddities.nl/n&o-159.pdf, December 2010.<br />
# Ary Boender: "Numbers and Oddities", issue 156, September 2010, pp. 15.<br />
# ''I doubt that "R" is a Navy service. The distance from Izhevsk (formerly Ustinov) to the nearset sea coasts is 1200 km. Only low frequencies are in use (3194//3321//4325) for 24 hrs operations. How could it reach ships in local daytime? Unlike clusters, it is not a propagation or navigation beacon. Unlike single "P" (RMP-Kaliningrad) naval station, it does not transmit any RTTY or CW messages. It is more similar to "The Pip" (3757;5448). In both cases, transmissions consist of a single letter (marker) in CW, and of short SSB voice messages, most probably for checking a readiness of network operators. I think that both "R" and "XP" are similar communications stations of Staffs of military districts (voenny okrug) of the Russian Army. The reliable coverage area would be up to 500 km, at least in local daytime.''<br />
# Cluster beacon "L" appeared on 7038.2 and 8494.2 kHz and was was first reported by the VERON Intruder Watch on June 29, 2011 at 1800 UTC. "L" was also active throughout July 2011. The first thoughts were that "L" transmitted from St Petersburg but so far there is no evidence to support this. It moved on July 23, 2011 to 7041.6 and 8497.9 kHz and again on July 24, 2011 to 7041.8 and 8497.8 kHz. ([[Ary Boender]]: "[http://www.numbersoddities.nl/N&O-165.pdf Number and Oddities]", issue 166, pp.7). Cluster beacon "L" is not the solitary letter beacon "L" that transmitted in the past from Tirana, Albania, given that Albania is now a member of NATO. At the same time, the 10 MHz "P" beacon moved 1 kHz up, from 10871.8 to 10872.8 kHz.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984, page=K2.<br />
# IARU R1 monitoring system: "[http://tinyurl.com/3t6po2c Intruder News from: July 28th 2011]"<br />
# ''A couple of years ago I had the chance to speak to a Russian naval radio operator who works on a Russian frigate. He confirmed to me that the channel markers are military stations, mostly used by the navy. His English was poor so I could not ask for more detailed info, and as I don't speak Russian, you can imagine that it was a really nice conversation. I had to write down the morse characters of the call signs of the stations and he told me the locations. It was really fun, believe me :-) A couple of the markers that he mentioned have now disappeared but still exist as cluster beacons. The radio operator identified 'L' as St.Petersburg, 'P' as Kaliningrad (HQ of the Baltic Fleet), 'S' as Arkhangelsk and 'C' as Moscow (naval HQ). He knew that there were more stations but didn't know which ones because they were not relevant for his vessel.'' [[Ary Boender]]: "32nd edition of the N&O column / Spooks newsletter", December 24, 2000 [http://www.cvni.net/radio/nsnl/nsnl032/nsnl32mx.html].<br />
# IARU R1 monitoring system, September 2016 [http://www.iarums-r1.org/iarums/news2016/news1609.pdf]<br />
# William I. Orr, W6SAI: "High Frequency Single-Letter Beacons (SLBs); Part 1: The K- and U-Beacons, The Search Goes On", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, December 1984, pages 28-31.<br />
# ENIGMA-2000, Issue 109, November 2018, page 16.<br />
<br />
==Further reading==<br />
# Schimmel, D.W.: "The underground frequency guide", HighText Publications, Inc., ISBN 1-878707-17-5, 1994.<br />
# Harry L. Helms, W5HLH: How to tune the secret shortwave spectrum, Tab Books, Inc., ISBN 0-8306-1185-1, 1981, pp. 141–143.<br />
# "SLHFB (Single letter high frequency beacons)", ''The SPEEDX reference guide to the Utilities'', SPEEDX, 1984.<br />
# [http://mailman.qth.net/mailman/listinfo/spooks Spooks] mailing list. <br />
# [http://www.numbersoddities.nl/ Numbers and Oddities]: Ary Boender compiles this monthly bulletin with reception reports of various mysterious transmissions and makes it available for download at his personal web site.<br />
# Mike G.: "Single letter cluster beacons", ENIGMA Newsletter #14, January 1998, pages 31-33.<br />
# Simon Mason: "New revelations about single letter transmissions (MX)", ENIGMA Newsletter #16, January 1999, pages 39-40.<br />
# William I. Orr, W6SAI: "Those Mysterious High Frequency Single-Letter Beacons (SLBs); Part 2: The Cluster Beacons – A Soviet Riddle!", ''[[Popular Communications]]'',CQ Communications, Inc, ISSN 0733-3315, January 1985, pages 22-24.<br />
# William I. Orr, W6SAI: "The Cluster Beacons Revisited; An Inside Look at Nine Puzzling Channels", ''[[Popular Communications]]'', CQ Communications, Inc, ISSN 0733-3315, February 1985, pages 38-40.<br />
# Enigma Control List [http://www.ominous-valve.com/enigma.txt], Enigma-2000, May 2005.<br />
# Fritz Nusser: "[http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/beaconsandclusterbeacons/index.html Channel Markers and Cluster Beacons]", ''[http://www.astrosol.ch/index.html Fascinatning Shortwaves]'' (2001-2009)<br />
<br />
==External links==<br />
# [http://www.youtube.com/watch?v=3o1Ox5-UIeg Moscow's "C" Single Letter Cluster Beacon 7.390MHz 40mtr ham band], using a FT-817 HF tranceiver (Youtube video).<br />
# [http://www.youtube.com/watch?v=zrVcLd9jHpk Letter Beacon "D"] on 5153.7 kHz using a Sangean 909 portable receiver (Youtube video).<br />
<br />
{{CC-BY-SA-WP|Letter_beacon}}<br />
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[[Category:Beacons]]</div>SV1XV