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Bill Hohnstein Said :
> That's not necessarily true--lightning can easily arc over egg
> insulators. Doing that, the lightning can damage the concrete at
> the guy anchors. So, even metal guy cables broken with insulators
> should be grounded at their lower end.
> One broadcast radio station that I worked for had a light display
> during every storm. Even when there was no local lightning this
> base insulated tower would discharge the static build up via its
> guy insulators arcing over (even with a static drain at its base).
> When this happened at night people would sometimes stop and watch the
> "light show." This hazardous situation was eliminated by placing RF
> chokes across the guy insulators...
I agree with Bill!
My reference was to the normal ham tower installation wich "IS NOT
INSULATED AT THE BASE."
When the base is insulated, the guy wires become the more attractive path
to earth.
A tower in concrete, connected to a ground system, has lower inductance
than any of the other paths on the tower. Continuous grounded guys make it
better for the lightning but not so good for the antenna patterns.
73, Kurt
YagiStress - The Ultimate Mechanical Design Software for Yagi's
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