Hello,
Since starting to use my "big boy" amp, I have had more antenna problems than
in all my 40 years + of ham radio.
Examples:
1. Those cheap black plastic insulators commonly sold at hamfests melt. The
result is the antenna falls.
2. A small tree branch (1/4" dia.) fell from a tree and was hanging from the
end of the antenna (I just happened to notice this). The first time I put power
to the antenna, the 12ga stranded copper wire melted at that point and the
antenna fell down. I found the small branch on the ground and it showed signs
of having been on fire.
3. The latest happening is the strangest (I swear it is true). After tuning up
the amp into a dummy load, I switched to the antenna to fine tune the amp
settings. While fine tuning, everything looked normal then all of a sudden, all
the amp meters went wild. My first thought was "damn, one of those paracites,
how will I ever get rid of it". Then I went back to the dummy load, and every
thing was back to normal. I immediately went out into the yard and found the
antenna on the ground. The 12" by 1" ceramic end insulator was broken at the
antenna end. I could not visually find any defects in the insulator at the
failure point.
Is all this being caused by corona effects? What could be the max voltage at
the antenna ends? Copperweld appears to be the only way to go for wire, but
what should I be using for end insulators?
Any insight would be greatly appreciated.
Bruce,
W3BP
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