Hello gang ...
I have had an chance to talk to some of you on this subject in the past.
With summer here in the south we seem to be having our share of storms.
Up to last week I have had no verified strikes to my tower. I have
started my grounding project and expect to make a big dent in finalizing
it in the next couple of weeks. With 165' of metal looming above my
house, and 4 runs of 7/8" and 2 runs or 1 5/8" hardline aimed at my
house and shack I want to make it as safe as humanly possible. I have
received 2 hits/neat hits based on my polyphaser strikes counter in the
last 2 weeks. All runs of hardline are protected with polyphasers on a
copper bulk head under the tower. The bulk head is grounded to a 10'
ground rod which bleeds off to 2 additional 10' rods at the base of the
two tower legs located away from the house. I plan to ground the
electrical and phone service to a ground ring that will circle the
house. I will also add a tree from each tower leg. All will be commonly
grounded.
Strikes can't be stopped. We need to make the strikes that do occur, as
safe for personnel and property as possible. I am not lucky enough to
be able to disconnect radios as storms pass. Several nodes operate off
the towers and are unmaned while I work. I just have to plan for the
worse and keep good insurance.
To relate a story of one strike withnessed as a school child, we were in
a 5th story school building and watched a bolt of lightning strike the
one story police station across the street. The antenna was mounted in
the middle of the flat roof and poorly if grounded at all. The antenna
was 10' lower than all buildings surrounding the police station. The
strike vaporized the antenna and a fire ball about 2' round blew out the
front door of the police station blowing the alum screen door off its
hinges and rolled in the middle of the street and disappeared. Needless
to say we sat on the inner most wall of the room for the remainder of
the storm.
I'm sure the safest means is to disconnect all antennas and control
wires but short of that, more grounding can reduce the chances of
damage. I still think that disconnected coax inside a room only invites
a strike that will find ground. It might be the radio across the room,
the wiring on the other side of the wall, or plumbing pipes in the next
room. I still say Ground, Ground, Ground!!!
Good luck ... and stay safe!!!
Steve
KD4WIW
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E-mail: kd4wiw@ipass.net
Home Page: http://www.ipass.net/~kd4wiw
Packet: KD4WIW@W4RAL.#RTP.NC.USA.NOAM
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TOWERS ARE BEAUTIFUL !!!!
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