We had the same thing happen in V47 on our 160/80 inverted V's. We would
be cooking along and then boom the SWR would go up. Go outside in the
dark and find the dipole end on the ground. I don't think I have ever
seen this in Dry Colorado but on the beach with salt and water rope
didn't last too long. We were also sparking in the palms at the end
enough so that the security guy was concerned and pointed it out to us.
W0MU
On 11/29/2016 12:26 PM, Jim Brown wrote:
Yes. I first ran into this nearly ten years ago with the first 160/80
dipole that I rigged between trees. Like a dummy, I failed to use an
insulator between the ends of the dipole and the 5/16-in rope. When it
got wet, the rope melted and the dipole was on the ground.
The ends of any wire are a high voltage point, and should be treated
as such. This is also true of radials!
73, Jim K9YC
On Tue,11/29/2016 9:23 AM, Jeff DePolo wrote:
In high-power broadcast, we regularly see burn-outs caused by
weather-worn
fiberglass insulators that start to wick up water when it rains.
What used
to be mostly RF-transparent when dry becomes lossy when wet, with
airborne
contaminants, rust/oxidation, and whatever else aggravating the
condition
over time, ultimately leading to arc-over and/or mechanical failure.
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