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1231

Equipment / Re: Best MWDX antenna?

« on: June 07, 2021, 2345 UTC »

Now grounded to the top of the mast, too. Did the same thing I did at the bottom of the mast. A couple of F connectors, a female-to-female barrel connector, and a hose clamp. Yeah, it is a mechanical connection, but soldering at the top of a mast with wind blowing (and thunder in the background) did not seem like a fun idea.

Might go back out in a few to add a few snap-on ferrites, though AFAIK, most of the ones I have available currently are for higher frequencies. Whatever, I suppose.

I was also considering adding a few on-ground radials at the bottom of the mast. Like maybe four to eight 9' wires. Still undecided, though.

I will try to deploy the other miniwhip later this week or next, then take a closer look at MW with the phaser inline.

................

Update. A snap-on ferrites added, for whatever they might or might not help. I need to order some more mix 31 or 43 ferrites. I just do not like the price for large ones.

1232

Equipment / Re: Best MWDX antenna?

« on: June 05, 2021, 1041 UTC »

Still running in the background. Been listening to Asian DX on 40m SSB this morning, including currently an op from Papua New Guinea running 100w into whatever loop antenna.

1233

Equipment / Re: Best MWDX antenna?

« on: June 05, 2021, 0810 UTC »

Quickly skimming VLF and lower LW with the active miniwhip, I was able to spot Cutler at 24KHz, Aguada at 40.75KHz, and WWVB at 60KHz.

Rolled by a few beacons in LW. I would say my CW is limited, but it is more like nonexistent without a decoder. Morse code just does not work for me.

NavTex at 518KHz; probably Miami.

1234

Equipment / Re: Best MWDX antenna?

« on: June 05, 2021, 0503 UTC »

A quick screenshot of AM BCB. Well, a 725KHz portion of the band to be technical.

https://imgur.com/a/eCcJHWO

Current nighttime mediumwave noise appears to be hovering around -90dB at the bottom of the band to nearly -100dB at the top of the band. From a noise perspective, my community is somewhat rural, but my immediate neighborhood is more like a suburban area.

I am definitely going to need the second active antenna and the phasing unit to sort out the mediumwave jumble. Too bad the phaser only goes down to ~1MHz, but whatever I suppose. I am more of a casual mediumwave listener anyway.

I would do a screenshot comparison with another antenna, like my 148' LoG, though the feedlines for those are across the house. I try to do a comparison at some later time.

1235

Equipment / Re: Best MWDX antenna?

« on: June 05, 2021, 0445 UTC »

Deployed one active miniwhip. Have another one to go. I am using a PA0NHC-derived design built with SMD parts via the Transverters-Store.

https://www.ebay.com/itm/222469570201

I did not bother much with selecting a spot. I just put it at the back lot line away from the house. Mast is a 10.5' fence top rail buried about 3' in the ground. I might extend the height later, but I have to take some care due to tropical weather. I really not too interested in installing guylines, either.

The antenna is working. I am listening to 20m SSB contacts at 0428z ranging from California to Russia. Noise floor on 20m is averaging under -120dB according to my AirSpy HF+ Discovery. Not bad IMO. :)

I am not even using any ferrites on the feedline, and the the coax is only grounded to the base of the mast. It was getting dark outside when finishing up the coax run. I do have a KD9SV RF common mode choke rated for 3000-ohms+ resistance at .5-10MHz back near the receiver.

I intend to ground the antenna at the top of the mast as intended by the design, plus probably install a few ferrites. Maybe tomorrow.

1236

Equipment / Re: Best MWDX antenna?

« on: June 05, 2021, 0413 UTC »

Pretty nice for inside. :)

BTW, I was able to quote and view the pics, though note they are not showing up here at HFU. The host might be blocking them at third-party sites.

1237

Equipment / Re: a easy 22m dipole.

« on: June 05, 2021, 0411 UTC »

A horizontal dipole can be hard to beat for simplicity of design and deployment, though note height can make a considerable difference on performance and directivity.

http://www.n3fjp.com/antennas/dipoles.html

If you can not get it a half wavelength - about 36' - or better above ground, then you might fair better for DX with a vertical antenna.

1238

Software / Re: SDR# ISM Device Plugin

« on: June 02, 2021, 0402 UTC »

Going a step further I suspect it could be interesting in a mobile with a small UHF vertical driving around a densely populated area, or even stationary in such a location with a small yagi or similar directional antenna.

1239

Propagation / Re: E Season

« on: June 02, 2021, 0334 UTC »

0334z at night and 11m is hopping with activity. Not even a SDR or desktop receiver needed here. I am in the den right now using just a basic eBay SI4732 receiver and a 9' vertical ground mounted over a four 9' radials in the backyard.

1240

Equipment / Re: 630M Loop on the Ground (LoG) antenna

« on: June 01, 2021, 2201 UTC »

It is often my primary HF antenna under 15MHz for regional reception out to like 1000-1500 miles. It works quite nicely for stateside 80m-40m monitoring.

The primary lobe of reception is upwards. Think more or less NVIS for 160m-40m. It can receive DX, but a low-hanging NVIS dipole can as well depending upon propagation.

Performance rolls off pretty fast above 15MHz. A preamp can extend it further upwards if desired, though it probably breaks into numerous lobes at upper HF among other considerations, so it can become a huge YMMV compared to even something as simple as a 9' vertical.

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