Bill WA4FKI wrote
"For some reason my K9AY lost it's directivity, seems to receiver well in
all directions.
When I built it the apex was and still is 35 feet off ground with the bottom
of the K9AY about 8 feet from the ground. It is grounded there with a 5 ft
ground rod. To my knowledge nothing has changed. Any comments?"
Bill, I have built several hundred K9AYs over the past 8 years and I would
aggree with Ralph, that you may have lost your ground connexion; other
possible causes are, ground dried out, you can supplement the earth rod with
a 4 radial counterpoise ( each wire 10m ) laid on the ground. Another
possible cause could be loss of relay control voltage, poor relay contacts
or open circuit or too high termination resistance or a failure of remote
varible termination ( Vactrol of LDR/LED ). Also make sure the ground side
of the 9:1 matching transformer is good and check that you haven't got an
open curcuit or high resistance loops, or corrosion on any loop/earth/feeder
connections and make sure the feeder to the Rx hasn't got an open curcuit
screen connexion.
Finnaly, you could bench test the Head and Control units to make sure that
the relays and termination are all okay.
73
Andy Ikin
Wellbrook Communications
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