My electric service is underground, running about 450' from the service
transformer to the polebarn garage in the rear of the property. At that point
there is a SPG for the electric service, but then the power lines, again
buried, run 70 feet to the house, which is a modular home on I-beams mounted
upon a cement block foundation. There is NO electrical ground at the house,
but the telephone line, also buried from the roadside service box [over 200
feet away] has a ground rod driven into the soil next to the house.
The entrance for the electric line and the telephone service are at the NE of
My radio room is located near the SW corner of the house, and I will have all
lines [coax, rotor control, etc] running out through a vent panel in the
foundation immediately below the radio room.
What I am considering is adding a SPG for the RF cables, etc., at or near to
the vent panel in the foundation at the feed-through point.
Not sure if having the SPG for RF very distant from the electric service SPG is
inviting problems. [yes, I know, that's contradictory, as you cannot have TWO
Any thoughts on this would be invited, as I will be installing all my towers,
radial systems, antennas, etc., in the Spring.
This one's easy Don. I believe there ought to be a ground rod at the entrance
to the house but I'm no NEC expert. No harm in putting one in and connecting
it to the house entrance panel's ground (not the neutral). I'd install a rod
for your arrestors and shack ground at the cable entrance. I'd then run a wire
(I use #4 bare solid.) around the perimeter, avoiding sharp corners to the
telephone rod. I'd also run a wire outdoors to the new entrance ground or, if
not that, then back out to the barn's entrance rod. I'd also tie my towers'
ground systems to the SPG system, whether that be at the house or at the barn.
You really, in a bad way, want to tie all these grounds together, except if
your tower is hundreds of feet away then you just leave it on it's own (I have
one 500 feet from the house that is not really tied to anything else.
And the single SPG, is a misnomer, you can have more than one. For example, at
my cable entrance, I have so many arrestors and the like, I actually have three
rods, spaced about three feet apart, all tied to together, onto which I attach
all my stuff. One can never ever have too much grounding or too many ground
Phil - KB9CRY
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