The new NEC code requires Radio Towers ( It not related to any particular
service to be bonded and grounded. Wither your code official is up to speed
is a matter of where you are. Because my Matt foundation was so large it
required a commercial inspection and he passed it and 55 yard of 3000 Ibs.
mix is in the hole. It's not only bonded with very large copper cable to the
rebar it will also be a #6 ring and run out a total of 36 feet. Useing 10
foot commercialt ground rods. Standard cell tower system. I planning since I
have the Hard line Kits to ground it at the top of the tower and then at the
bottom before the 100 foot run under ground to a bussbar and poly ground
plate system on the coax lines. Depends on how large of a strike I take if
their will be damage. Like all good hams I will try my best. Champion Radio
Products use to sell a book on the subject and made for a lot of information
on the subject. They still might as I brought my copy years ago and it not
like the stuff change all that much. 73 Gene K2QWD
----- Original Message -----
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
To: <ai4wm@yahoo.com>
Cc: "Perry - K4PWO" <k4pwo@comcast.net>; <towertalk@contesting.com>
Sent: Monday, October 06, 2008 10:13 PM
Subject: Re: [TowerTalk] house entrance ground for RF ground?
> Bill MacLane wrote:
>> The service entrance grounding conductor required by the NEC is for
>> safety, not rf grounding, not lightning protection, only safety.
>> Properly installed grounding conductors are to prevent a fault current
>> from burning up things (including your house) or flowing through ones
>> body.
>>
> A good ground fault detector will do the latter, but not a good ground.
> New systems use GFIs that are sensitive enough to grab the wires without
> feeling a shock (they tell me) and I've seen a demonstration. Me? I
> don't have quite that much faith in them.
>> A good RF ground system is bonded to the service entrance electrical
>> ground rod for the same reason. A good ground system made of several
>> ground rods, copper strap and radials and it will dissipate a strike, but
>> it will not assure complete safety from a strike. I know. I rebuilt
>> many commercial radio transmitters, STL, and microwave links (as well as
>> a station) after a strike and every station had tons more copper burried
>> than any ham radio operator's shack. Recently there was a series of
>> articles on lightning protection in QST. I have also run across some on
>> the internet.
>>
>>
> I'm using 32 or 33(lost count) 8' ground rods, cadwelded(TM) to over
> 600 feet of bare #2 copper. That also ties into the house electrical
> system as added protection for the house. The top of the system is at
> 130 feet and it's taken quite a few *verified* direct hits. Until last
> year it was averaging 3 a year, but non last year and none this
> year...so far. I should add, there are lightning strikes and then there
> are lightning strikes. All strikes are not created equal and I doubt
> much is going to withstand a direct hit from one of the so called super
> strikes. Actually I have two complete systems tied together. The shop
> and house have separate electric feeds and panels, but all of the ground
> systems are tied together into one very large network. And yes, I did
> that before copper went up over five times its value in 2000.
>
> 73
>
> Roger (K8RI)
>> 73,
>> Bill
>> AI4WM
>>
>>
>
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