Guys,
I put out a request for info about possible "stacking" problems . I
wanted to "stack" a Cushcraft 40 meter rotary dipole parallel to the
boom of my 4 element Gem quad and one foot above it. Many of you
responded, thanks.
Well I did it . The results are that there is no interaction on any of
the 5 quad bands and no detectable interaction of the quad boom with the
rotary dipole. Strange enough, this is what was predicted by K6STI's AO
software. The manufacturer said there would be severe detuning of the
dipole. Others of you predicted that at worse one would have to retune
the dipole, relative to it operating by itself.
I tried to gauge the interaction by first hanging the dipole from the
tower at 30'. Then I lowered the quad to 30' and took swr curves with
the dipole absent. Next I married the two. There was no change in
either the dipole's or quads SWR curves. Hot dog! Cranked it up to 75'
and all was still well.
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