Steve:
Thanks for pointing that out - commercial installations using a shield
ground lead just before the suppressor outside the building. I don't recall
seeing an instruction sheet with the Polyphaser suppressors I bought
advising this connection. But as I described, I already have the three coax
shields grounded just before they hit the suppressors out at the tower.
(I'd rather keep the lightning in my back yard away from the house than
conduct it closer to the shack before it's shunted by the suppressors.) I
also have the shields grounded at a SPG plate in a steel box just outside
the shack window.
73 de
Gene Smar AD3F
-----Original Message-----
From: K7LXC@aol.com <K7LXC@aol.com>
To: SPELUNK.SUENO@prodigy.net <SPELUNK.SUENO@prodigy.net>;
towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Wednesday, May 15, 2002 10:07 AM
Subject: Re: [Towertalk] Lightning Protection - Conclusion (for me, anyway)
>In a message dated 5/14/02 5:02:44 PM Pacific Daylight Time,
>SPELUNK.SUENO@prodigy.net writes:
>
>> My original query (Must I ground the coax shield ahead of the
>> Polyphaser suppressor?) is one of those
angels-dancing-on-the-head-of-a-pin
>> kind of thing.
>
> Not really. The answer is "yes". Commercial installations do just
that -
>I'm sure that that's in the Polyphaser book and other grounding references.
A
>ground kit is installed on the shield and connected to the building entry
>ground bus before the transient protector.
>
>> It'll never be answered objectively (quantitatively.) So
>> I'm going to have to be satisfied in knowing that I have grounded the
coax
>> shields at the top and bottom of the tower and I have installed
suppressors
>> on all coax (as well as control cables) coming from said tower. If a
>strike
>> takes out one or more PL259's I'll just marvel at nature's fury and
replace
>> the coax/connectors (and whatever else.)
>>
> You still need the shield to be grounded at the building entry as per
>above.
>
>Cheers,
>Steve K7LXC
>TOWER TECH -
>Professional tower services for commercial and amateur
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