Hi Scott,
You are not the only one with the problem you mention.
Checking my KT-36 today, I have resonance at
14.068 1.8 SWR 95 ohms R 0 ohms X
20.937 1.0 SWR 52 ohms R 0 ohms X
27.497 1.1 SWR 43 ohms R 1 ohm X
(NO, I am not trying for the 11 m band!)
As far as I can recall, when installed about 12 years ago, it was in
the middle of the band, but obviously is low now, especially on 15 and
10 meters.
I am fairly sure there is no problem with water. The only thing I can
think of is the balun.
If you discover anything, please pass it along!
Thanks.
73,
Ken, W8EK
w5wz@w5wz.com wrote on 1/14/2022 3:13 PM:
Some recent queries to TowerTalk and the responses all pointed toward
bad coax/water in coax, or loose connections between balun and front
driven element and/or rear-driven element.
On 1/13/22, we tested the coax and even pulled up a brand new run to
test with. Swept both runs of coax from top of the tower with AA-54,
bottom end connected to a dummy load. Both runs of coax sweep
identically to the dummy load. Connect either run to the antenna,
experience the same symptoms of low SWR being low on all bands.
A call to M2 support; they suggested perhaps water in one or more of
the capacitors. We tilted the tower over to access the capacitors.
Removed all 16 end caps, finding no water. We did, however, find much
insect debris and dirt dauber nests. Cleaned all that out with
compressed air and a long rod to push through the 3/8" inner tube.
We also verified all the mechanical connections on the driven elements
and confirmed good continuity with an ohmmeter.
The SWR curves moved up in frequency, but the minimum point is still
well below the bottom of each band.
Other thoughts or ideas?
--Scott, W5WZ
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