Telamon wrote in message
For lightning protection you would need an additional ground at the
side of the house where the antenna coax comes in besides the antenna
ground. At that ground the coax shield would be connected and a shunt
protection device like a gas tube would connect the center conductor to
the same ground. For the lightning ground to be complete you would have
to bring the AC mains power to the radio to this same ground. The mains
ground is also connected to this ground. The supply and return AC mains
wires would have shunt protection devices to this same ground and
between them. Now all wires to the radio will be referenced to the same
ground at the side of the house and lightning induced voltage will be
equalized at that ground on all wires going to the radio. I donšt know
the electrical code in this regard and this side of the house lightning
ground may have to be the power entrance to the house to be legal. If a
big storm is coming I think most people would be better off
disconnecting the antenna and power to the radio.
I guess it would be ok, if you installed a ground window. But here, I
see no point to separate the grounds. If I had noise on a power line
ground to the house, I would still probably receive it anyway using
any other ground, being the ground conductivity is pretty good here. I
don't ground my radios to the power line ground normally, so thats
something I don't have to worry about.
Actually, I normally don't ground my radio at all. It's grounded
through the antenna ground. Thats the only one I use. When using the
dipoles, I'm not grounded at all. Nada...
I guess this method is ok as long as all precautions are taken.
"ground window"
But still, overall, I don't like unbonded grounds. We have tons of
lightning here, even in the winter. Using separate grounds around here
is asking for big trouble. I guess one reason my views differ, is I
don't use random wires, or other transformer fed antennas. Even my
160m inv L is directly fed, and has a good match as is. I have a
ground system under that antenna, but it's also tied into all the
other grounding around the house. I don't get any power line noise on
that antenna even though I'm bonded to all grounds in the area. My
main concern about the multiple grounds is lightning related. I see
many that ask about using multiple unbonded grounds, etc, unrelated to
this thread. Most of the time, I consider it a bad idea. So does the
NEC. I always disconnect all lines and ground them outside at my
"ground window" when we have lightning in the area. I see no point in
gas tubes, because even if I had them, I would still unhook. Lightning
makes me paranoid...
I've taken two strikes to my mast in the last
4 years or so. No damage at all so far..And the lightning strikes
about 10-15 ft away from where I'm sitting. MK