The KY6R Top Band RX Antenna Challenge: Final Results and Report!

The best 160M receive antenna was a total accident. I had my DX Engineering DV-40-P switched in the “Both” or 180 degree position and heard the weak signal DX with -130 dB noise. That’s 10 dB less noise than my second place RX antenna, and 20 dB less noise than my third place RX antenna. It also seems less prone to QSB than the other antennas. The signal seems to stay above the noise – even when there is fading. I was able to build ONE antenna last summer that matched this – it was a K6SE Flag, but instead of feeding it on one side with a resistor at the other end – I ran coax to both ends and brought those into a DX Engineering NCC-1 (or NCC-2).

My second place RX antenna is the Wellbrook ALA1530LNP Loop. As I said, its 10 dB noisier than the DXE DV-40-P, but when put in Diversity Receive and used as a second RX port antenna – with the DV-40-P, now we have a little more noise, but less QSB – when one antenna is affected by the QSB, the other picks up the slack. Its a great sound in my headphones, by the way!

Third place is the “Mod Bob”. It is much better than the old Cushcraft MA160V on receive, but is still below the other two RX antennas. HOWEVER, when fed against the Wellbrook ALA1530LNP, some real “magic” happens. The two together are only 10 dB noisier than just the DV-40-P, so like the Wellbrook alone, but the signal now is much better than the DV-40-P.

Here is a list of all of the antennas that I tried in the past year:

  1. Home brewed RX loop a la ARRL Antenna Handbook and with a W8JI improved feed. In fact, I tried phasing these through the DXE NCC-1 and NCC-2. Just OK – not worth it. I even built tuned circuits at the feed – and that just made them noisier. I also tried adding W7IUV preamps – same noise issue
  2. Flag and pennant – pretty weak and very noisy (I’m sure its my QTH and my neighbors houses)
  3. RBOG – showed some promise but pales in comparison to what I have now
  4. Phased 20′ hatted verticals with tuned circuits – phased through NCC-1 and NCC-2. Similar to the EWE fed with two “vertical dipole” like feeds, but the “dual fed EWE” was a much easier antenna to put up – two fiberglass masts and wire
  5. 60′ top loaded vertical – noisy
  6. MA160V – noisy

The most critical hint and tip is to get your RX antenna as far away from ANY house or building that has electrical wiring in it. The WORST you can do is put a RX up on top of your roof – where every heating duct, rain gutter and electrical wire can trash it with noise. Computer monitors, cable modems and routers, wall warts and dimmer switches (even in their “off” position) will make you hate 160M. Steer clear!

The Elecraft P3 is my best tool to measure noise and “SNR”. Read up on SNR – at W8JI’s wonderful site.

My year long “Top Band RX Antenna Challenge” are now complete, and as I start hearing the LU’s call CQ DX on 160M (their winter), it brings back fond memories of last summer, when I worked 5 new ones on Top Band, pretty much to my amazement (and delight)!

I put a ton of work in testing just about every possibility of RX antenna in my back yard – and now I have that all “dialed in”.

Next up is my Mod Bob remote tuner project – and THIS is why I love ham radio (way) more than awards chasing!, and believe me I have had a blast chasing awards – but that has run its course. These projects are picking up where the award chasing is leaving off.

 

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