While in preparations for IARU, one of which was getting the antennas
ready, Andy KC7DZZ and I came upon a problem. The 10m vertical dipole
and the 40m inverted vee have fine SWR's, but the 20m inverted vee has a
3.5:1 SWR. However, that 3.5:1 occurs around 14260, and on either side
of that, the SWR goes up to 4.5 or 5:1 on the band edges. This seems to
act like it is resonant on 14260. We have checked for anything touching
the wire on the end insulators, and also the center, which is up around
35 feet. On the center, the only thing that could possibly be touching
is a real narrow piece of string which doesn't appear to be
touching...appears only to be touching the center insulator.
We have checked the coax for a short, and there wasn't one.
A little background on the antenna:
It was up previously, resonant right around 14270, and had been working
fine. Then one support fell and we just put it back up today in the
same spot it had been. Now we have the SWR problem that wasn't there
before.
Any suggestions as to what could cause this?
Thanks and 73
David Jones, KK7GW
kk7gw@hotmail.com
Trustee for the Juanita Contesting Club-KD7BWU
jcontesting@hotmail.com
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