Hi Phil,
Impressive antenna you have there!
> I have had a large
> vacuum variable capacitor
> in place to do the job for several years, but lightning took its
> toll
> last spring. I thought I had
> ample protection...a 350uh choke across the base insulators to drain
> off static build-up,
OK, that's good
> and
> three sets of spark-gap balls; one on each tower leg across the
> insulators. This worked well
> through many storms.
I would use *pointed* spark gap hardware vs the round ones.
Electrical charges tend to accumulate where the curvature of a
conductor is greatest. So, a pointed object would have the
greatest curvature vs a round one....that's why lightning rods
are shaped the way they are.
> I have another vacuum variable ready to mount;
>
> 800pf @ 18 kv, 150 amps.
> Any ideas on how to keep this beauty from falling prey to Mother
> Nature?
Set the spark gaps as close as you can without arcing under normal
transmitting voltage. Protect the gaps with a rain hood.
Other than shorting out the capacitor when it's not in use, there
isn't much else one can do. Mother Nature does what she wants! :)
73,
Charlie N0TT
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