First time this has happen to me.
Yesterday evening we had snow and ice on everything, including my dacron
guy lines for my 60 ft top loaded 160m vertical. When I transmitted on the
vertical, my SWR was about 3.5:1. I went out to the vertical with a dust
brush and dusted off the snow off the vertical connections, feed wire, etc
at its base. As expected, it did not change anything. I did find that my
min SWR point/resonance had gone down about 75khz to 1.755 mhz. There was
nothing I could do.
Later in the evening when it stopped snowing and a bit drier outside, the
resonate point had gone up to 1.75 mhz. It was late, so I went to bed. Too
bad, I was hearing IV3PRK and PE5T. Today I transmitted on the vertical and
found all was normal. My resonate point was about 1.820 as it should be.
I am guessing that since there are no insulators on the dacron guy lines,
and because of the thick, heavy ice and snow, the guy lines were conducting
enough to change my resonate point. My fix will be to place egg insulators
in the dacron lines a few inches from the vertical attachment point. BTW,
the vertical is made of 30 ft of 3" and 4" irrigation pipe, guyed at 30 and
I didn't think dacron would conduct with ice on it. Has anyone else had
this experience? Does my conclusion sound correct?
Chino Valley, AZ
4780 ft ASL
15 miles north of Prescott
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