Pete.. I put in a peripheral ground system, but I didn't have to dig a trench.
I used my gas edger to cut a slot in the lawn from the AC service entrance
around the house to my SPG box, and then for good measure I continued the rest
of the way around with the exception of the driveway. For that, I used a 4"
wide concrete block chisel to cut a 3" - 5" deep slot in the blacktop where it
meets the concrete garage floor pan. I laid a full circle of #4 solid copper
around, with ground rods every 15-20 feet along the length of it. Everything is
tied to this peripheral ground....the service ground (I put in a second one, I
didn't know how long the first one had been in) plus the ground rods for the
vertical and the tower. There are rods every 15 - 20 feet along every leg
longer than that, and three rods in a string on each leg of the tower. Every
piece of equipment in the shack is tied to the same ground bus, which goes
direct to the SPG.
It was a lot of work, but I think it was worth it.
73, Jerry K3BZ
----- Original Message -----
From: Pete Smith
To: towertalk@contesting.com
Sent: Thursday, July 29, 2004 9:39 AM
Subject: Re: [TowerTalk] Grounding, Lightning & corona discharge
At 09:03 AM 7/29/2004, Tom Rauch wrote:
>A single ground wire from the shunt protection is clamped to
>the power line ground.
>
>This is the national code.
Illustrative of the difficulties of doing the single-point ground thing
properly with an old house, our telephone and cable TV connections are 180
degrees around the house from the AC power entrance, grounded to a rod at
that point, so there is undoubtedly a fair amount of resistance between the
two grounds. Just to further complicate things, our telephones are in
parallel to the telco box rather than in series.
I would have to trench in a perimeter ground, per Polyphaser
recommendations, before anything else would begin to make sense.
73, Pete N4ZR
The World HF Contest Station Database
was updated on June 5, 2004
2728 contest stations at
www.pvrc.org/WCSD/WCSDsearch.htm
_______________________________________________
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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