I'm inclined to agree , RF getting in the radio . If you were TXing on SSB , the receiving op could probably hear the RF symptoms . Could be from leaky coax , or just proximity to the antenna . Coax is cheap , I'd be inclined to replace it with something better shielded . A good RF ground near where the cable comes thru the wall might fix you up , the splice point would be an easy place to try . What's your power supply ?
First thing getting replaced: The coax. I'm getting a new run of it (Right length) in the next week or so.Originally Posted by W5RB
I also forgot, and this would most likely be an important part of the equation: This is an attic dipole, so, the legs are not out 90 degrees. More like a horizontal V.
Power supply is an older Pyramid 25A, switching, I think.
You must have a big attic . You're almost certainly radiating RF from the antenna back into the radio . Any way to get the antenna outside ?
It might better to make one of those with four wire rotor cable. A friend made one, It worked well.. But its an all day tuning affair..
Yeah, big attic. Like 30 ft across and 70ft down or so. Working on getting the antenna outside, but will have to wait for the big run of cable to come in first.
Do you get RF burns off of the chassis when key down?
Nope. Which is why I never bothered with an RF ground. I just figured it would introduce more problems.
In the case of second floor shacks, I agree.
I'm still leaning towards RF feedback into the shack / radio / power supply on 20m. Possibly something attached to the radio or tuner that is close to 1/4 wave (16 feet) in length. Proximity to antenna is also not good.
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Hm, several things come to mind here. I'm starting to think maybe I should remove the UPS from the link as well here, since the power for the radio + power supply + UPS power line comes close to 16ft of cabling in all (6, 6 and 6).
You might also try about six turns of coax where it joins the fan (if you have enough coax).
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