In a message dated 98-07-14 16:31:16 EDT, oberjc@northsidecomp.com writes:
<< I want to place a grounded 25' metallic mast on the peak of my house
as a center support for wire antennas. I would like to use a relatively
thin (but sufficiently strong) gage of phyllistran or dacron rope to guy
the mast rather than using wire cable. The top of the mast will be up
about 55', which is higher than I've been able to raise antenna wires
between trees in the past, so I expect I'm increasing my odds for a
lightening hit.
It seems to me if lightening did hit this mast, wet phyllistran or
dacron guys might fail by melting if they conduct even a small percentage
of the current surge. Could this happen? Has this happened? Or can I depend
on a proper mast ground to safely conduct enough energy to spare such guys?
>>
Well, Phillystran has been installed for the last 20 years on towers in
Florida and other lightning-prone spots. They have experienced no failures
like you describe.
The black dacron rope is woven and will soak up rain water. I don't
know if it will actually melt if it were hit by lightning. If your mast takes
a hit, it's probably toast anyway and you won't have to worry about the guys.
Cheers, Steve K7LXC
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