I am replacing my switchbox and coax in my 4 high, 15 meter system. The
antennas are 4 element W2PV antennas using a gamma match with a variable
cap. After attaching new feed lines (odd multiple of a 1/4 wavelength) to
each antenna (and adding in another 1/4 wavelength to make a multiple of a
1/2 wavelength for measurement with a 259B), I discovered that one antenna
was out of whack with the others (higher swr and much lower resonant point).
Now since the bottom 3 antennas are on the same mast and rotate together
from the base of the tower (as opposed to the top one that is on a separate
rotator) I can't turn any of the lower antennas say 90 degrees from the
other 3 (to try an decouple antennas). The antennas are exactly alike so
should I set all the gamma caps the same or should I try and adjust the
gamma caps individually to get the same resonant point and will I get a lot
of mutual coupling? Antennas are at 40', 80' 120' and 160'. Anyone with
any experience along those lines?
Mike W9RE
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