Regarding unhooking the coax connectors, take a look at the following
excerpt from the Polyphaser engineering notes at
http://www.polyphaser.com/ppc_PEN1016.asp:
------------------------------------------
Just a word to those who tell us that they are safe from lightning because
they always disconnect the coax from their equipment. When asked what they
do with the disconnected line(s), they usually respond that it is placed on
the floor. Now if you stop and think about the last few thousand feet that
the lightning has jumped, you can see the fallacy of their thinking. In
fact, they made it worse since arcing involves ignition temperature plasmas
inside your house. True, the radio may still work, if it survives the house
fire. Throwing the coax out the window is not a solution, especially if the
coax has already entered the house from the antenna or the antenna is roof
mounted without a ground path. Grounding switches will not last long with
direct hits unless other good ground paths are provided. Grounding the
antenna line and not disconnecting the coax shield can still allow strike
energy to be shared with the equipment The shield connects to the chassis
and if a single point ground is not present with power/telephone protectors,
the equipment will be damaged.
------------------------------------------
Keith
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of jerryc
Sent: Tuesday, July 06, 2004 4:42 PM
To: TowerTalk@contesting.com
Subject: Re: [TowerTalk] Lighting
Tom
I may be wrong but my take on this is that many of us were told that
structures not properly grounded would build up static and be more likely to
attract a strike. I have also wondered about the fact that tall grounded
structures could attract a hit.
I went the route of the best grounding I could afford and polyphasers on all
coax cables. BUT I still unhook during thunderstorms (I am not weathy
enough to chance a hit with my hard urned equipment).
JerryC
KC8TES
----- Original Message -----
From: "Tom Rauch" <w8ji@contesting.com>
To: "Wilson Lui" <wilsonlui@atitec.com>; "'David Robbins K1TTT'"
<k1ttt@arrl.net>; <towertalk@contesting.com>
Sent: Tuesday, July 06, 2004 5:07 PM
Subject: Re: [TowerTalk] Lighting
> Thanks Dave and Wilson.
>
> > Grounding does not prevent strikes. What a proper
> grounding system does do
> > is allow for any lightning strike that does happen is
> condected safely into
> > the surrounding soil and not arc through any
> equipment/structure trying to
> > find a lower resistance path to earth.
>
> That's my opinion also, based only on the physics involved.
>
> I notice a large group of people actually think lighting
> does not hit grounded structures because grounding causes
> the charges to bleed off or dissipate.
>
> I'm curious where that idea actually came from. Does anyone
> know?
>
> 73 Tom
>
>
> _______________________________________________
>
> 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.
_______________________________________________
TowerTalk mailing list
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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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