I use a comtek systems hybred coupler with 4 1/4 wave top loaded verticals in
an 80 meter array. Testing the system out before the winter season, I've
found that the array's resonant point has jump 400KHz to apprx 3.990MHz from
where each individual antennas are tuned at +- 15KHz at 3.600MHz. The array
has always jumped 200KHz, over three rebuilds, using various lengths of
verticals and top loading wires. So this major jump on the surface is
unexplained. In looking over the array, I have decided to replace the
feedline connections as some were getting weathered. I also recently put up
a 4 foot tall 3,800 foot goat wire fence on the west side of the array just
past the 1/4 wave ground radial field. Could this be the culprit in all of
this. I am wondering if anyone with a 1/4 wave vertical array has ever
noticed such a change and if so, what caused it-. In my research, I have
found most arrays constructed like mine jump around 100KHz from where the
individual antennas are tuned due to interaction inside the array, phasing,
and factors in the environment. The explanation for mine originally going up
200KHz was that it was in the clear without anything around it- And it worked
great! Now a simple fence is causing it to jump 400KHz???? Can't be that
simple????
It's either the 1. Fence 2. Feedlines are screwed up 3. Comtek Box problem
4. One of the verticals is screwed up but this has been ruled out- 5. Your
suggestion here??
The F/B is down a bit, no matter where I am on the band-
73 Paul N0AH/7
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