I saw the one post on this topic about PolyPhaser saying grounds further apart
than 75 feet "don't (effectively) see each other" during a lightning strike
event even though they are bonded together. I assume this is attributable to
the propagation delay (LC time constants) between the distant points as
compared to the lightning strike rise and fall waveform.
Brings up an interesting question for my own situation. My tower is next to a
detached garage. The electrical inspector insisted that my tower, and it's
grounding system of radials and rods plus a UFER, be bonded to the sub-panel in
the garage for safety per NEC 810. This sub-panel is bonded to the house
service panel by the bare copper conductor in the underground feeder to the
garage.
But it's 75 ft between the house and the garage, plus the house service panel
is on the opposite side of the house. So that's a run of about 150 ft between
the tower and the house service panel, half if which is along the basement
ceiling.
I wonder if bonding the tower to my home electrical system in this fashion is
helping or hurting me if Thor decides to visit?
This fall I want to re-do my coax runs and change the entry point to the
basement, mid-way between the opposite sides of the house. I was thinking of
running some #4 solid from the tower radial grounding system all the way around
the house to the service entrance ground rod. But this might make things worse
by creating a loop that might magnetically couple with the stroke currents?
Sometimes it's really hard to get a good SPG for everything unless you're
fortunate enough to be starting from scratch with a new house design..
OBTW... I control my rotor via Bluetooth. Power for the rotor comes from the
garage.
Before I put up my tower, I had one direct hit on a 40M wire V-Beam fed with
window line. When I'm not operating I took that feeder off the entry panel and
put it out in the middle of the yard with a brick on it. Came home to find the
antenna on the ground. The window line was like a wet noodle. No copper left
in it....just plastic with cracks where the vaporized copper had departed.
The brick was laying at the bottom of a 1 foot hole in the yard. Nothing in
the house was affected. But the cat was never quite the same after that when a
storm came up.
N3AE
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