[Antennas] Distortion problem on quad while trying to work VP6

[Brad Johnson]

Marty,

Sounds like you are experiencing RFI in your audio chain. I am curious why
you have to use a tuner on your 5 band quad. What is the SWR on 15 meters
without the tuner? My guess is that it must be high for some reason.
Ideally, each element of a quad should be fed individually with each loop
having its own matching stub. Feeding a quad in any other manner is asking
for trouble (in my opinion) An antenna tuner only fools the transmitter into
thinking it is connected into a resonant load...high SWR will still exist in
the transmission cable and can increase the likelihood of RF getting back
into the shack.

If you are using a mic with a preamp, turn it off. If you are using
processing, turn it off....still having trouble? May need to improve station
grounding. The best solution would be to do what ever necessary to get the
quad resonant on frequencies you want use. Quads are good antennas, but
there are people out there selling them with deficient feeding mechanisms I
have been there and done that with a quad myself.

Good luck

73,

Brad
AA5CH