The whole question here about grounding is really one of expense. Clearly
the best setup is to ground everything together from the tower to the shack
with 0 gauge or larger wire. All bonds must present virtually 0 resistance.
Even .001 ohms is too high with a direct lightning strike. Commercial
stations spend hundreds of thousands of dollars doing this and they do it
well.
On the other hand, for an amateur station on a reasonable budget, grounding
to the necessary level becomes expensive and possibly impractical. The next
best solution is to disconnect everything.
The first 5 years I lived at my Franklinton QTH, I lost from $1000 to $2000
a year in electronic equipment from nearby lightning strikes. I had the
best grounding I could make, and all kinds of MOV lightning protectors
including a whole house 3 legged protector at the power line entrance. In
fact my home owners insurance threated to cancel me. I then went to a 100%
disconnect setup. This meant that all my electronic equipment was
disconnected from power lines, phone line, rotor control, everything. I
brought all these lines into my home through a a metal plate and
disconnected everything at the plate. Well, I lived there for another 15
years and never, I repeat never had another problem from lightning.
Carl Moreschi N4PY
121 Little Bell Drive
Bell Mountain
Hays, NC 28635
----- Original Message -----
From: "Mike Gorniak" <mgorniak@genesiswireless.us>
To: <tentec@contesting.com>
Sent: Friday, January 26, 2007 7:09 PM
Subject: Re: [TenTec] Station Grounding
> Agreed! For the life of me, I will Never understand why there is so much
> debate in the Ham Radio Community regarding this issue. In the
> Professional World, there is no debate at all. We look very foolish to
> outsiders when we incessantly and incorrectly pontificate about matters
> that have already been settled from an engineering perspective. The NEC
> requires all grounds to be bonded. Just do it. You'll be a lot safer. As
> AA4NU suggests, Polyphasor is a good resource. Here's another:
>
> http://www.nautel.com/Resources/Docs/Whitepapers/lightningprotection.pdf
>
> I apologize to those that have seen this debate here before. However, my
> conscience requires that I comment when I know that people are putting
> themselves and their families at risk.
>
> Stay Safe! 73,
> Mike,
> NM7X
>
> ~Original Message~
>
> Date: Fri, 26 Jan 2007 12:28:08 -0500 (EST)
> From: Billy Cox <aa4nu@ix.netcom.com>
>
> Here we go AGAIN ... on grounding. The problem is most "ham"
> grounding setups don't meet codes and are poorly constructed.
>
> Check the sources who know, like the Polyphaser site. Less than
> accurate advice on this topic can lead to some serious damage.
>
> The commercial sites don't run out and disconnect everything
> when the clouds form. Ditto for the VHF/UHF ham FM systems.
>
> The goal IS to everything at the same potential by having them
> common. Keep them apart and they WILL be at different potentials.
>
> That IS a recipe for damage.
>
>
> --
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>
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