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[TowerTalk] Re: Lightning & parasitic elements arcing

To: <towertalk@contesting.com>
Subject: [TowerTalk] Re: Lightning & parasitic elements arcing
From: n4zr@contesting.com (Pete Smith)
Date: Mon Jun 2 16:11:05 2003
At 06:40 AM 6/2/03 -0700, Jim McDonald wrote:
>1. Ignore it - it's a good static drain.
>
>2. Rent a boom truck and ground the centers of the parasitic elements on the
>40M yagi.
>
>I have seen four direct hits during a 30-minute period in one storm here in
>Arizona, and probably others have occurred too.  No apparent damage.  Have
>several 8' rods at the base and in a coax/control line trench to the shack,
>ICE protectors on the coax cables, rotor line, and DX Engineering switch
>cables, and the ground rods connected to a large horse arena pipe fence near
>the tower.  Use mostly Cadwelds to connect wire to rods.


A third option, suggested to me by W8JI, is to ground the centers of the 
elements through inductors that are large enough to be effectively open 
circuits on 40, thus avoiding any serendipitous creation of new interaction 
modes among your antennas.  This could also be useful if you ever decided 
to shunt feed the tower on 160, in which case you could develop some fairly 
large voltages at the top of the tower and cause arcing problems -- that 
was the context in which Tom suggested it to me.


73, Pete N4ZR
The World HF Contest Station Database was updated 9 May 03.
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