Charles wrote:
> I disagree with u, Dick, on two points at least:
>
> 1. routing coax thru PVC, I have seen two problems with this, one is
> water sitting in the pipe if it has any horiz. parts to it, and the
> other,
> bigger problem, is the possibility of the PVC catching on fire in the
> event of lightning hitting and heating up that area. The PVC that I
> have
> burned, burns brightly even after the heat source is gone--dangerous.
>
Shouldn't this be prevented from happening if a ground wire (or better
yet, low inductance flat ground strap) is run from the tower base along
side (and burried below) the antenna cables and is terminated at the
ground rod outside the shack wall, which is then connected to the
bulkhead? Doesn't the lightning surge current basically get shunted to
ground if this arrangement is used?
> 2. Placing the bulkhead inside the interior walls or on them
> ("between
> the studs") means u are placing things that will catch fire very near
> a
> hot spot if lightning wants to heat it. I would not take the chance.
>
> When lightning hit my shack one time, it lit up several cables inthe
> window
> sill, and I had a five inch flame burning in my lower window frame!
>
Did you have your entry panel grounded outside the shack to a ground
rod?
> I recommend passing the coax bulkhead fittings thru (mounting them in)
> an
> insulating, fireproof panel. Disconnect all incoming wires to the
> rigs.
> 73, K4VUD
>
regards,
Dave
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