If you have a Polyphaser installed at the bulkhead entrance to the shack,
the chance of this happening is extremely small. With the arrestor in place
we are talking hundreds or thousands of volts rather than millions or
billions inside the shack. This is not necessarily true if the arrestor is
located at the base of the tower rather than entrance to shack.
A better solution is to ground the center conductor (along with shield) to
common ground system that has low inductance to an outside single point
ground system.
Keith NM5G
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Joe - WDØM
Sent: Monday, September 13, 2004 9:06 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Grounding control cable/Rotator control box
Here's a web site to consider, when it comes to disconnecting coaxial cables
from equipment:
http://www.polyphaser.com/ppc_PEN1016.asp
The quote pertaining, is toward the bottom/middle of the page, and reads
thusly:
"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. "
73,
Joe
WDØM
At 08:00 AM 9/13/2004, Dale L Martin wrote:
>On Sun, 12 Sep 2004 22:14:42 -0600
> "Noel" <yaesurig@msn.com> wrote:
>>Had a pretty good lightening storm here this evening and decided to
>>disconnect my coax cables after I heard that familiar ticking sound
>>that told me there was static charge buildup on the coax.
>
>
>hmmm....
>
>I learned this lesson a few years ago:
>
>There are three sounds that help to remind me to disconnect cables:
>1. The sound of distant and approaching thunder 2. The click the
>light switch as I leave the radio room 3. The click of my bedside
>table lamp at night 4. The starting of my car engine in the garage
>
>73,
>dale, kg5u
>
>
>
>
>_______________________________________________
>
>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
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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