Setting up my first Beverage, looking for input

[Beam Tetrode]

Hey folks,

I'll be setting up my first Beverage sometime this week (when the wire spool finally arrives).
I've read through many resources, Including W8JI's construction manual and the ARRL Low Band DXing book.

However, these books are written by Hams for Hams.
I am not interested in listening to bored retires talk about their grand kids
and their glaucoma medications , I want to use it to listen to Pirates.
Does anyone in the Pirate community have any piraty tips for me?

Would a jolly roger help?

Should I use discarded peg legs for supports?

Thanks in advance.

[SW-J]

Loop - have you tried building a loop? ... a 2' to maybe even a 4' diameter tuned loop ... you won't be disappointed ... ONLY if you've never tried one and seen how quiet they are compared to dipoles or verticals (not sure about a Beverage tho), if you have tried a loop, disregard this post  . I tried a vertical about a month ago here at the QTH, full 1/4 Lamda vertical, 35' straight up cut/tuned for 6.93 MHz with ground radials ... and - MAN was that thing noisy!!! QRN out the wazoo ... worse, far worse than the dipole even ...

     Technical/advanced hobbyists and theorists only - verifying/measuring vertical antenna resonance:
     http://www.youtube.com/watch?v=OD2cslsbrQ0

Anyway -

This simple loop version worked pretty darn good, I've tried sizes from 1' diameter to 3' diameter:

  http://www.mtmscientific.com/swloop.html

An article that is a little more technical; note also the coupling loop (to the receiver) is down low to the loop; this helps in coupling out a little more signal (real easy to try things; I used plastic clamps from home depot to 'mount' and move things like the coupling loop around for testing):

  http://www.qsl.net/pa3hbb/magloop2.htm

Added:

You do realize, that this is not a good low-angle antenna, and for DX on HF you could have an incoming signal at 20 degrees elevation (from W8JI site; vertical omni included for comparison):

Antenna Type        RDF  (dB)      20-degree forward gain (dBi)   Average Gain (dBi)
---------------    -----------     ----------------------------     ----------------------
1/2wl Beverage           4.52                 -20.28                               -24.8

Vertical Omni, 60
   1/4wl radials           5.05                     1.9                                  -3.15


Also - your link for W8KI site is broken


  (Here's how a link should be embedded in text on a Simple Machines BB:

  [ url=http://somesite/]Site Name[ /url ]     <-- Note: No double quotes

  Just take out the three spaces I added near the URLs!)

[cmradio]

As one that has low-band DX'd for just under 30 years, I will toss in my vote for a loop unless you live in a **very** quiet location.

Peace!

[Zoidberg]

So far the best low noise/high signal strength reception I've heard - judging from audio clips posted by various pirate DXers - has come from, in no particular order:

• Full wavelength HF loops (check with HFU logs for user ID "desmoface", located in Ohio)
• T2FD (hamsters love to gnaw this bone of contention to death as being inefficient for transmitting, but SWLs seem to report they're generally satisfied with the design)
• Exotic less-than-full-wavelength loops, flags and pennants (KAZ and others)

I use a smallish indoor magnetic loop (around 3' wide by 6' high) made from coaxial cable mostly to tame high suburban RFI.  It's only the best compromise for my particular situation, and far from the best antenna.  I got better reception with a cheap Radio Shack random wire kit in the rural area where I used to live, but you do what you have to for the conditions.

[Beam Tetrode]

Thanks for the replys guys.
I just moved onto a nice big property in the middle of the Yukon Wilderness.
There is little to know RFI neer me and everything I want to hear is to the South
so the beverage's directivity is a big plus. 

[Token]

OK, first of all small loops are going to be more quiet than many other types of antennas.  However, keep in mind that part of the reason is that small loops are also very inefficient.

Small loops are great if you can not put up a full sized antenna or if you want a second, directional, antenna that can null noise sources.

In general the physically larger the antenna the more signal you will pull in, it is simply about capture area or aperture.  So a large antenna will get signals that a small loop cannot.  Of course the noise floor will often come up also, but signal to noise is the key, not an absolute lack of noise or not.  And very large antennas, even simple wire antennas, can exhibit directionality that must be taken into account.  If the main lobes of an antenna are in directions you can not use, and nulls are in important directions, then it will seem the antenna is not working well, when the antenna is really just fine, but the installation is less than optimal.

A good, low noise, large antenna is a full wave sky loop.  One cut for 80 meters and about 20 to 30 feet off the ground will work very well for receive applications from AM BCB to about 20 MHz.  It works above that freq, but will be best below 20.  This antenna would be laid out in a square about 64 feet on a side.  Actually, it should be a circle, but a square is a good compromise between support simplicity and performance, it could even be an equilateral triangle, but you would start to get some pretty noticeable nulls in the coverage.

The Beverage is a fine antenna, but if built as a true Beverage it will also have some directionality, so keep this in mind during your planning stage.

[Tube Shortwave]

A bev antenna is used for LW and AM BCB bands because signals approach it at very low angles.  If you use a bev for 7 megs, the signals will be coming in from a much higher angle, and you will actually have negative 'gain' compared to a dipole at the high angles. 

However, this is a good time to point out that experimentation is what it's all about.  So, if you want to find out for yourself, go for it!

The best antennas I have used for 7 MHz. area SWLing are-

Large inverted L (over lots of ground wires, fed with 9:1 balun)
T2FD (horizontal, flat config.)
1/2 wave wire dipole (with 1:1 balun feed)

Verticals are OK, if you have LOTS of ground radials and are in a quiet location (I am).  But, even the simplest dipoles outperform a vertical for SWLing, hands down.

Seriously, I know the 'expert hams' hate T2FD antennas, we hashed it out a little here not too long ago.  However, for SWLing, they are really quiet, and really pull in the signals!  Sometimes, I can hear things on the T2FD that I cannot hear on the other 5 antennas.  I don't care how they transmit, just talking about SWL applications here. 

73!

[SW-J]

Verticals are OK, if you have LOTS of ground radials and are in a quiet location (I am).  But, even the simplest dipoles outperform a vertical for SWLing, hands down.

Ground radials can be elevated (located several feet above physical earth)* along with the antenna feed point ... if you are going to actually mount the vertical at __ground__ level (at the level of local physical earth) then the requirement for 'LOTS' of ground radials arises ... for receive, I am going to state that this is not nearly as critical, it makes a BIG difference on the GROUND losses during transmit for sure, but on receive you are 'working' with a signal to noise level already establish by the local and ionospheric environment (as in "QRN" vis-a-vis lighting 'static' discharges) in a similar manner that a small tuned loop works (physically small, but working with a S/N ratio established by 'outside factors').


And AS noted above, the vertical _was_ the nosiest antenna I have ever used ... I cannot emphasize how noisy it was, and this was with direct comparison against 3' receive tuned loop and the dipole ... so I make this statement quite beyond simply repeating the experiences of others   
 

*Reference:

Found it - "HF vertical ground systems experiments"
http://www.antennasbyn6lf.com/2008/08/hf-vertical-gro.html

"Beginning about a year ago I set up a test range in my pasture and began a series of careful experiments on HF verticals with various ground systems including some with elevated radials.  Two results stand out.  First the NEC prediction that a few elevated radials can be as efficient as a large number of ground radials seems to be correct at least at my site with the test antennas I used."

[ChrisSmolinski]

I'll second (or third) loop antennas in general. I put up a 132 ft T2FD about 2 years ago, and was quite pleased with the results. Lower signal levels than my various dipoles, but much lower noise levels, so an overall improvement in the SNR.

A few months ago I put up a roughly 635 ft horizontal loop antenna, which is about 20 to 40 ft above the ground, in a roughly rectangular shape. The goal was to have something with better MW reception than the T2FD. So far, it seems to be working well for that, also for HF.  I am anxious to try it on LW this winter.

[weaksigs]

Just a few more comments concerning your beverage antenna possibility.

From where you are a beverage erected in the proper direction should work very well.
If you terminate the beverage properly it becomes a wonder antenna for frequencies with a minimum of one 1 wavelength of wire or more up to around 10 Mhz where other antennas usually take over as a better choice. I have heard them personally demonstrated on several occasions and instantly became green with envy when a beverage was compared to almost any other antenna, again for stations in the design direction and at the lower frequencies. From your distance reception (beam width) will widen out appropriately to cover most of the lower forty I would think.

Look on an amateur radio website W8JI.com for some realistic comments and installation hints. My own advice would include;

1)   Static dissipation with a dc ground must be provided lest your receiver front end go quiet without a whimper. I’ve seen snow static light up florescent bulbs in my own shack when living up north. Beware!
2)   Beverages work best (and must be) very close to the ground, however up there make sure the moose population can get underneath or it may not last long. It may need to be 15 feet or more off the ground and they work fine if covered with snow.

The advice given by others which includes using a loop of proper design is quite valid and I would build a loop even if you do erect a beverage. You always need more than one antenna and especially in your case where cold wire comes down in the middle of winter. You may also want to erect a long insulated wire on ground as they also provide low noise reception. I used to have a full wave of wire for 40 meter transmission while receiving on a quarter wave of wire on the ground. Great s/n ratio!

The very best to you and keep us informed how you make out.
Many hours of good listening to you sir!

One note- I just noticed that you had read the articles on W8JI's site. Believe me his advice and experience on low band reception can be used to your advantage. Not all of us blab and whine about our number of or the effects of our medications but some may just be in a position to help and assist from a technological standpoint.

Stay warm 

weaksigs

[SW-J]

Rhombic - I'm surprised no one mentioned the Rhombic (including me  ). I thought of it about a week after my first response ...

If you have the room (real estate), the Rhombic can do what I think you want the Beverage to do: directionality.

The Rhombic will give you directionality, but also doesn't have the limitation of a  'low angle of reception'.

A little more info:

  http://www.tpub.com/neets/book10/42o.htm


Some interesting history on/of Rhombics:

  http://web.archive.org/web/20011116030212/users.neca.com/cummings/rhombic.html


Edit: Spelling!

[cmradio]

Thanks for the link!

I've wanted to learn more about rhombics

Peace!

[weaksigs]

Beverage demo on 1.816 Mhz
Here is a link that demonstrates the reception between an inverted "L"
antenna and a 720 ft beverage. The beverage is oriented at 55 degrees
from a site in Massachusetts and the demo is performed at 4:00 pm local.

The guy talks a lot but you can hear the signal difference when the
antennas are switched for an "A" - "B" antenna comparison.

Lets us know your beverage plans and please share your experiences.

Have you also investigated "pennant" and "flag" antennas?

Cheers- weaksigs

[Token]

Rhombic - I'm surprised no one mentioned the Rhombic (including me  ). I thought of it about a weak after my first response ...

If you have the room (real estate), the Rhombic can do what I think you want the Beverage to do: directionality.

The Rhombic will give you directionality, but also doesn't have the limitation of a  'low angle of reception'.

I did not mention the Rhombic because I was not aware he was looking for directionality.  In fact that was why I mentioned beware the directionality of the Beverage, or plan for it.

I have three Rhombics myself, and absolutely love them.  One is a 450 footer pointed 270 deg true (South Pacific, Malaysia area, and Australia for me), another 450 footer pointed 035 deg true (Europe, Middle East, and N Africa for me), and the last is a 300 footer pointed 310 deg true (China).

Each of mine has a switched 800 Ohm termination (600 Watt non-inductive, but for receive only use a 1 Watt carbon resistor would be fine) that can be controlled from the listening desk.  This means with the termination selected the antenna is directional along its primary axis, but when I switch the termination out the antenna becomes bi-directional, along the axis and reciprocal.  This gives me directions of 270 and 090 on one, 310 and 130 on another, and 035 and 215 on the other.

When terminated the Rhombics are also fairly low noise antennas.

The 450 footers are about 240 feet per leg length, which means at 20 MHz the gain is roughly 12 dBd, at 10 MHz the gain is roughly 9 dBd, and at 6 MHz it is roughly 7 dBd.  The 300 footer has legs about 168 feet long, meaning about 10 dBd at 20 MHz, 7 dBd at 10 MHz, and 5 dBd at 6 MHz.  Those are calculations, not measurements.  In the bi-directional mode subtract 3 dB from each of those numbers.

My Rhombics are not really optimized, I built them more to my property constraints than anything else.  So, the enclosed angles are not quiet as good as they should be, but pretty close.  For example, the 270 deg antenna is 450 feet long and 190 feet across the wide part, it really should be more like 220.  Also, they really should be higher.  Here I have them at about 30 feet, they would work better if I had them more like 50 feet.  But, as we clock winds of 100 MPH about once a year in the region (although I have not seen that at the house) I keep them fairly low and survivable.

I also have a couple of wire V-beams that work well and are again directional.  The nice thing about a V-beam is that you only need one tall support (at the apex), but the supports at the far ends can be low, say 8 feet.

I still say that if I for some reason I could only have one antenna, and I need it to be for general use and omni directional, it would be a horizontal sky loop, made as large as I could get away with.  I would want at least 60 feet per side, and a height of 25 feet or more.  I am, however, very glad I am not limited to one antenna.

[SW-J]

I did not mention the Rhombic because I was not aware he was looking for directionality.  In fact that was why I mentioned beware the directionality of the Beverage, or plan for it.

I put two and two together and deduced from his location ('Yukon wilderness') and his inclination towards a beverage that he might be desiring some directionality and gain back into the states ... the original suggestion towards a loop was made before Beam revealed he had 'nice big property'  so ... he could build something with some nice gain *and* directionality too, sounds like a prescription written for a Rhombic!

Token, Beam's original query was about construction details, poles/suppots (peg legs  ) and such - what did you use to hoist/hold your Rhombics up?