In a message dated 3/22/04 8:43:26 AM Eastern Standard Time, shr@swtexas.net
writes:
>>We
have all observed a storm cell moving towards us that was
generating lots of strikes. As the cell neared our towers the
lightning stopped and the guy wires started crackling and popping.
As the cell passed on by the lightning would resume. CLEARLY
the towers were doing something to reduce the incidence of
strikes in the immediate vicinity. Whether the little "do-hickeys"
at the top of the tower are helpful or not is another issue. The
spikes occupy a pretty small volume of air compared to a number
of stacked HF antennas with grounded elements.<<
Thanks John for another "vote" (OK, more evidence) that there is something to
the "umbrella" effect in eliminating or reducing strikes over "protected"
area.
I think we have another case when hams helped to discover valuable effect,
phenomena. Who else is putting up "umbrellas" to check it out? We have noticed
the difference between being hit when having lone verticals of spiky towers vs.
towers with big antennas on the top acting like a plate of capacitor and
"collecting" charge from the area and taking it to the ground, reducing the
potential differential, diffusing formation of the leader, making it less
"attractive" for lightning to hit. Experiences with before and after situations
are more
than just pure luck. This was observed in different parts and noticed by few
people, so clearly not a product of our imagination. Worth trying? I think so.
Just eliminate sharp, lone masts protruding over your antenna "hats".
I tried to bring this phenomena to the Florida U "expert" group, send them
email, offered to cooperate. No answer, they know better, they are busy
figuring
how to attract lightning and feed it to ground, rather than to repel it. I
guess it brings the bucks in the never ending quest for ...?
73, Yuri, K3BU.us
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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