Well - personally I prefer one handy dandy ground for everything but the
safety ground in the house wiring. Since they figured out that several of my
hiker friends who were found dead near lightning
blasted trees had been killed by induced currents, I have had my antennas
well away from my house(s). I do not want to be within fifty feet of a
lightning strike unless I'm in a Faraday cage, period.
I have a conventional (per Polyphaser) lightning ground system here at the
house, and well casing grounds through the center of the tower bases at the
farm. I went to the well grounds because a ham who does the maintainence for
the Mississippi Highway patrol said well casing grounds stopped lightning
damage to the MHP repeaters. There's a lightning arrestor at the lightning
ground on each coax and each control cable, along with .01 6KV caps between
each control wire and ground.
A current balun, a ferrite balun, at the shack side of the arrestors, and a
lightning arrestor and balun at the bulkhead at the shack keeps stray RF out
at the antenna and out of the shack. So one ground system acts as both a
lightning ground and an extremely effective RF ground.
The coax between the towers and the bulkhead into the shack are cold to RF.
As are the rotor control lines, the remote switch lines, etc., etc. My
shack(s) are fed from their own breaker box - and the safety ground (the bare
or green wire in the Romex) in the breaker box has both a direct connection
to the service ground under the meter base. There is no separate ground
return from the shack because that would form a ground loop.
I have had this system up since New Years day of 1989, the first tower at the
farm has been up three years. Both towers get hit once or twice a year. Once
while I was operating. There was no damage to antennas, rigs, cables or
anything else - other than some scorch marks on the tower galvanizing.
As a result, I consider my grounding systems satisfactory.
73 Pete Allen AC5E
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