Tom,
When I was a young-un (in 1966) I had an old school beverage antenna
suspended between a 40 ft pole and an 80 ft tree some 150 ft away, as with many
antennas in those days it was made of whatever wire I could find and in this
case it was ground wire used by the telephone company ... #6 I believe and it
was a real task keeping this thing up due to its weight alone.
In those days I just disconnected the antenna from the radios and grounded it,
also tied to the ground was a brute force AC line filter that helped clean up
and regulate my ostensibly 120 v mains.
One day we had a bag storm.. you know one of the real gut busters with lottsa
lightening sideways rain and the whole deal. Needless to say it hit my antenna
somewhere in the middle and I found it laying in the yard after the storm. A
friend (wa3kgc) and I went out and grabbed the melted ends and attempted to
pull it together and low and behold whouldnt you know it it was short about 40
ft. Now this damn wire was as big as my finger.. how could this be. Well we
took the antenna down and measured it ... added enough wire to bring it back to
the correct length and put it back up in the air.
WHen I went into the basement I found the brute force filter had also exploded
and since it was in a metal case there were chards of metal that had gone
through the rafters in my basement and the filter had totally gone. Luckily I
had the forsight to disconnect the radios and they were safe.
I have seen antennas destroyed several times since that time (not mine however)
and have observed one interesting fact, antennas with a higher impedance seem
to be hit more than lower inpedance ones.. better than a 2 to one margin I
would say.
Jim WA3MEJ
Message: 5
Date: Sun, 8 Jul 2012 09:34:27 -0400
From: "Tom W8JI" < w8ji@w8ji.com >
Subject: Topband: Lightning makes antennas vanish
To: < Topband@contesting.com >
Message-ID: <C03E04344D964684815C90E9E0D1B22C@tom0c1d32a93f0>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
I've never experienced this before a year or so ago, when I had a Beverage
antenna melt in two from a nearby tree getting hit.
About a month ago I had about 300 feet of a Beverage just vanish from a hit
on a tree next to the wire.
Now it happened again this week, and long stretches of two Beverages just
vanished. This is cad plated #17 electric fence wire.
Anyone else have this happen? My copperweld #14, that clearly has arc
pitting where it passed over other wires, shows no damage other than the arc
pits. The cad-steel fence wire must get so hot it just vaporizes. I can't
even find any pieces of it.
Since the 1960's or 70's, this is the very first time I've seen this happen.
Are thunderstorms more violent now, or is wire cheaper? :-)
I'm not fixing my antennas until October or November.
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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