I just put up a K9AY loop, using the Array Solutions control boxes, and
am pretty disappointed. There is no audible or visible difference in
the noise level, while the received signal strength is down whenever I
A/B it with my inverted L. There does seem to be a little directivity,
but not much, and subjectively I find that weak signals are all heard
better on the transmit antenna. Judging by results in the current
contest, I've got an alligator on my hands!
The preamp amplifies by a couple of S units, and I can hear the relays
out at the antenna switching when I change directions or termination
resistances, although gain and directivity do not change noticeably.
From this I assume there's nothing wrong with the electronics
I tried to do my installation "by the book." Ground is provided at the
base of the antenna by a 6-foot ground rod. There are two common-mode
chokes on the feedline, one at each end of approximately 100 feet of
RG-6. About the only deviation from the published design is that the
top of the crossed loops is at 28 feet, not 25, and the loops have their
bases more or less horizontal, where the published designs show them
tilting upward approximately 15-20 degrees from the center in each
direction. I can make that happen with some more rigging, but before I
do that, I'm looking for suggestions of other places to look for the
problem.
--
73, Pete N4ZR
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