Thanks to all for the very helpful review of lightning protection
and grounding principles! Here is what I have learned from this
and am about to apply.
Context:
The only reason I am extending the ground is because the shack
entry point for antennas is 48 feet away from the service ground rod.
I understand that I need to connect to that to avoid circulating currents.
The tower will be heavily grounded so hopefully most of the energy
will be absorbed there. The ground here is said to be Alkaline (sand,
some clay and limestone) and the test I just ran confirms that.
Plans:
I will go with copper ground rods and avoid complications. The wire I
have is stranded and each strand looks to be about #10.
I am awaiting a reply from Harger as to the cost and part numbers I
need for the CADweld moulds, starter and materials. I am told that
Harger is 1/2 to 1/3 cheaper than all other sources.
I will have a grounding panel just outside the shack wall, about 24"
from the wall, through which all of the antenna and rotor lines will be
routed. My one open-wire feedline will have both a disconnect knife
switch and inline AEI lightning protection fuses. The coax and rotor
wires will have Polyphaser and MOV protectors. The panel will be
thoroughly bonded to the buried ground line that I will have extended
from the service panel ground rod to the shack entry point 48 feet
away.
I think that about covers it.
- Thanks! & 73, DavidC K1YP
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