Hi All,
Let me toss my hat into the ring here and tell you my experiences about
lightning.
When I erected my two towers, I grounded them very well. There was an
article by a W5 out in West Texas that used a mixture of vermiculite and
other things to make his ground. The holes I dug were about two feet in
diameter and three feet deep for each tower. Three-quarter inch, 10 ft
lengths of copper tubing were used. The soil here in AZ is very dry so a
low impedance ground I thought was necessary.
The second thing I did was to provide a large surface area at the top of
each tower (ie, a Yagi with grounded elements) to dissipate the charge
build up. There is a company out of Chicago that makes ground screens for
towers who's sole purpose is to dissipate the charge build up caused by
passing storms. Their claim to fame was to dissipate the charge before the
electric field gradient was sufficient to cause a strike. In my opinion, it
works.
I followed these two ideas and I have never been hit in 24 years although
the grammar school about 400 yards to the West of me took a direct strike
about a year ago. I thought it was all over with when the sound and the
flash were at the same time.
This was not cheap either but so far it has worked beyond my expectations.
I know I have that article somewhere.........
73 Hardy N7RT
At 04:14 PM 7/5/06 -0500, Bill Aycock wrote:
>
>Keith-
>Your statement below the excerpt from Jim, (below) is NOT true. It is not a
>matter of bleeding off the entire charge field, it is only a matter of
>changing the distribution of the charge. Changing the contour of the
>potential field to make another place the weakest path is all you need.
>I know many "experts" put the idea of bleeding off charge down, but I have
>seen professionals in related fields give arguments just as well documented
>on the other side.
>Quit assuming the whole energy packet has to be controlled, and think about
>using finesse, instead.
>Bill-W4BSG
>
>At 03:03 PM 7/4/2006 -0500, Keith Dutson wrote:
>
>> >The measured energy of the strike is not the point here. The point is to
>>try and prevent the charge build up to where the strike occurs.
>>
>>Well, if you are going to prevent a strike, you basically have to bleed off
>>all of the strike energy. I don't think that is possible.
>>
>>73, Keith NM5G
>
>Bill Aycock - W4BSG
>Woodville, Alabama
>
>
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