That doesnt work for us that have solid rock as the tower base. My 180' has
solid granite at 8-14" below grade and the other 3 towers arent much better,
I think the deepest spot is 2' of sandy gravel.
The 80-100' pines make good lightning arresters and their roots are
horizontal. I push them over with a front end loader bucket.
Carl
KM1H
----- Original Message -----
From: "DAVID CUTHBERT" <telegrapher9@gmail.com>
To: "HAROLD SMITH JR" <w0rihps@sbcglobal.net>
Cc: <topband@contesting.com>
Sent: Friday, July 27, 2012 11:36 AM
Subject: Re: Topband: Lightning protection
>A low impedance tower ground is important. Google TOWER FOOTING RESISTANCE
> for an IEEE ppt. on this. I would aim for a couple of ohms. That means
> several long rods.
>
> Dave WX7G
> On Jul 27, 2012 9:06 AM, "HAROLD SMITH JR" <w0rihps@sbcglobal.net> wrote:
>
>> About 20 years ago I decided to do something about lightning protection.
>> My tower is 80 feet of Rohn 45G, with a 5el Telrex monoband 20 meter yagi
>> at 82
>> feet.
>>
>> Hygain 153BAS at 90 feet and Hygain 103BAS at 100 feet. I have a homemade
>> antenna
>>
>> switch box near the top.
>> I shunt feed the tower with an Omega Match for 160. The shunt rod is
>> 1/2inch EMT
>> conduit.
>>
>> I use vacuum variables in the Omega match.
>> At 65 feet I have a Diamond X200 for 2meter/440mhz. all cables come to
>> the
>> base
>> and go underground
>>
>> to a steel box at the entry to the house. The HF antennas are fed with
>> RG-17 and
>> go through an ICE
>>
>> 308 15kw coax arrestor. The X200 is fed with RG213 through a PolyPhaser
>> arrestor. The control wires
>>
>> all go through PolyPhaser arrestors. I made LC to UHF adapters.
>> My tower is the tallest thing for several miles. The tower is guyed with
>> 6700lb
>> Phillystrand.
>> So far so good.
>>
>> Price W0RI near St. Louis, MO
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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