in need of some thoughts on next things to try (HF antennas)

[Rob Seastrom]

Hi folks,

Need some ideas on next things to try.  I've got one of these antennas as an interim/compromise antenna (and one of the compromisiest of the large compromise antennas!) until my tower gets put up later this summer:

https://www.dxengineering.com/parts/pez-ef-8010-jrkw <https://www.dxengineering.com/parts/pez-ef-8010-jrkw>

It's up about 30 feet, in nowhere near the most optimal location (however it was convenient for hasty erection) and is mostly working satisfactorily for what it is - having mostly operated club stations I only established an LotW account in February and I'm now at a count of 89 for DXCC on a combination of FT8 and FT4.

As you might imagine being short it's not particularly broad on 80m.  I shortened it up to get the low point at the digital watering hole for 80m which still gets me an acceptable match up to 3670 or so.  The configuration is as follows:

Antenna + about 70 feet of LMR400 + Polyphaser on ground bar bonded to three cadwelded ground rods + 
10 feet of LMR400UF + LDG AT7000 + short piece of 8X + IC718 radio.  There is 1" ground braid coming in alongside the UF (same hole) bonding the tuner and the radio to the bus bar.

Now here's the part where things get interesting and I'm interested in thoughts for what to try next.

Tested into a dummy load, the radio works fine; small adjustments in drive power to get 40 watts out of digital signal on all bands.

Into the antenna with the tuner in place, I get a match on all bands, but something is limiting me to a little under 20 watts out on 40m only.  Presumably this is some kind of SWR protector.

If I substitute a cross needle meter for the tuner, I get the following matches, confirmed +/- with an MFJ 269:

1.5:1 swr on 80m. 1.9:1 on 40. 1.3:1 on 20. 1.2:1 on 15. 1.2:1 on 10.

So 40 is the worst match, and I'd be wondering about RF into the shack on the braid were it not for the ground bus bar and the lightning arrester.  I am not currently running a discrete counterpoise but have tried one before and it didn't seem to make any difference.  Willing to give it a shot again if you think it will help, interested in thoughts on where to put it vs. the antenna (back away from the antenna or in parallel to it underneath like a huge j-pole lying on the ground).

Interested in thoughts for what to try next.  Countries I'd like to work keep popping up on 40 and I wouldn't mind having the extra 3 dB that running 40 watts would represent.  It may be that the best approach is to wait until things are overtaken by events with the tower, but that is not the "fun" approach!

Anyone have any thoughts?

73 de AI4UC



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