Dave:
My comments embedded below.
73 de
Gene Smar AD3F
----- Original Message -----
From: "David J Windisch" <davidw@copper.net>
To: <TowerTalk@contesting.com>
Sent: Wednesday, May 26, 2004 5:45 AM
Subject: [TowerTalk] Power ground
> Hi, all concerned:
>
> My building-entry power ground (rod), here in Cincinnati is, well, in
> not-so-good condition, after years in service.
>
> The line comes in above grade to a corner of the building, through trees,
> from a pole 75 feet away at the county roadway.
>
> When the rod is replaced, would there be an additional lightning-strike
> safety benefit to adding "some number" of short radials to it?
Thin radial wires on the surface of the earth serve no useful prupose
regarding electrical safety of the service entrance. We hams use radials to
improve the coupling (capacitive) between the earth/dirt and our vertical
antenna current return path(s) at 1.8 + MHz. These thin wires will do
nothing to shunt to ground several hundred or more Amps of 60 Hz fault
current from the utility.
>
> What are the *technical* pros and cons of burying the line?
Pros: 1. Protected from falling tree branches; slightly better immunity
from RFI; 2. slightly lower vulnerability to lightning strike (the strike
still could enter the line from the nearby above-ground portion); 3. one
less conductive object in the near-field of your antenna(s); 4. (Others will
come to me after I hit send!)
Cons: 1. Possible to dig up the wires if the ground is ever tilled; 2. co$t
(power company isn't likely to do it free of charge); 3. co$t (you'll
probably have to change out your meter head to accommodate the wires
entering the meter housing from below, rather than above; 4. co$t to repair
if #1 occurs.
>
> Can physically-separated grounds be tied together with buried copper water
> pipe sections brazed together?
Yes, but compare the price of pipe vs using copper tape, available from
Polyphaser and others, or from your local scrap yard.
>
> TIA & 73,
>
> Dave, N3HE
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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