Last year, I purchased a second-hand KT34XA. I re-penetroxed all the tubing
joints and replaced all straps and capacitor end caps. The antenna performed
perfectly for several months.
Now, on 20 meters only, my SWR jumps abruptly between flat and 3:1. The
problem seems worse when the wind is up, and is also possibly
temperature-sensitive. When I put a few hundred watts into the 3:1 SWR, it
promptly drops to 1:1 and remains there for a while before jumping back up. 15
and 10 meters are totally unaffected.
A friend in Colorado, W0LSD, has the same problem with his XA.
I assume that there is a bad joint in the outer portion of one of the driven
elements. I'm assuming that a problem in a parasitic element would not
present these symptoms. I tightened all hardware on both driven elements, with
no success.
Have any of you XA-users ever experienced a similar problem?
Tony
KM0O
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