To save some (~250 feet) of wires and cables I am thinking of hanging a steel
wire with attached cables (coax and control) between the (near) top of my tower
directly to my radio shack located on the top floor of my house. Instead I can
pull all the cables down the tower, through a ditch i the ground and up along
the side the house up to my shack, with much better possibilities of good
protection from light-strikes.
The tower is well grounded (as far as I know, 9 grounding rods, Ufer ground and
whatever else) The house has a Faraday grounding cage with a total of 6
grounding spots (plus whatever it gets through the utility connections). The
lightning protect has been tested (by direct lightning strikes) at least twice.
Burn-marks to prove it.
I am planning to let the coax cables be grounded in the tower through a plate
equipped with bulkhead connectors and ground them at the house with a similar
plate - bulkhead connectors. That plate will be directly connected to the
lightning protection next to my shack. There are 4, thick, copper wires that
connects the lightning rods over my shack to the grounding rods four stories
down.
What I am afraid of is, in case of a lightning strike (direct hit or near-by),
the big open loop created by my overhead wires together with the tower, the
lightning protection of the house and the ground will induce enough current to
cause damages. This loop will have an about 70 x 125 feet opening, enough to
make it a good loop antenna (not the purpose though). (No I don't have any AM
stations around that will have their radiation pattern altered.)
Anyone with experience from this, or any objections? I would not like to find
my installation looking like a fried chicken after inclined weather.
73 de,
Hans - N2JFS
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