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Old January 31st 04, 10:41 AM
Mark Keith
 
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"Jack Painter" wrote in message news:LRySb.3240$gl2.2307@lakeread05...
Thanks to all responding. A 20m antenna on top of the tower was demolished,
pieces landing 100' away. That one single feedline was connected and
operating a wx-alert system in the shop.


Big omission... I now think the tower was hit, and piped the energy to
the wx-alert system which then routed it to the rest of the house via
the power wiring. Was that coax routed down to and snubbed to ground
at the base of the tower? From the damage, it almost sounds like it
was elevated in the air from the tower to the shop.

The house suffered zero structural
damage, the roofline and 2 antennas on it was definitely not the source of
any of the strikes. The outbuildings also suffered no structural damage or
even marks. The coax(s) most definitely carried the lightning, now whether
they got it from the ground current, tower, tower ground radials, that's
anybody's guess. Coming into the shop, that was likely from the 20 meter
feedline, but the explosion inside the shop right next to my friend was just
"energy", the same kind that blew up floor tile from a patch cord hanging on
a hook by itself. The computers destroyed were from energy in the AC wiring
and cable modem network.


I bet the wx-alert box was the point where it got into the ac wiring.
I just can't see lightning energy traveling towards the house on a
coax that is on the ground. Once the lightning is at ground, normally
it should stay there. It's where it wants to go. I don't see it
ignoring the ground and radials at the tower, and preferring to go
towards the house on the coax, if the coax wasn't even connected close
to the tower. "I assume it was unhooked, and just laying on the
ground."

From all I have read here, this hit was (luckily) one of rare intensity and
diversity. Two strikes to the tower later in the summer of last year had
only minor impact on anything.


I wouldn't leave any more unprotected feedlines hooked up during
storms. I think all would have been ok, if not for that. Or at least
assuming there was no strike on the power lines a short distance from
your house when this happened. MK