Hi Guy,
I definitely agree with you about not being cheap on the tower ground.
Back, a couple of weeks ago, i asked for advice about tower grounding
here, on the list. I received some good and well meaning advice, but some
of it isn't so good. There is a lot of mis-information and misunderstanding
about grounding. I would strongly recommend that everyone go to
www.polyphaser.com and read every page you can find there on it. Its time
well spent.
Last weekend, i rented a "mini-trencher" and trenched 725 ft. of the
backyard. There are 12 trenches, each going out like spokes from a wheels
hub, each 36 ft. long, under the main tower. There are 4 going out from the
smaller, housebracketed tower, also 36 ft. long each. The towers and the
utility ground will all be tied together as will the "singlepoint entry"
just outside the shack. Polyphaser is very clear that all grounds need to be
tied together.
While they recommend flat copper strap, they also recognize that many
parallel paths, all conductive, represent a low inductance ground, even if
its copper wire. I'm using #2 solid and 38 ground rods, 12 of them -8
footers, 26 of them -10 footers with threads and couplers to join some of
them. My ground system will be a combination of 20, 15 10 and 8 ft. rods.
All connections in the ground will be exothermically welded(Cadweld).
While some might ridicule my ground system, i'll sleep better and have the
knowledge that i've got a ground that can "take-it", and keep on ticking.
IMO, better to spend the money up front.
Will also have "whole-house" protection from the "utility" under the meter
base and individual transient protectors at outlets throughout the house as
well as gas discharge tubes on the coax, and the coax will be grounded at
the top and bottom of the towers and at the "single-point entry" point.
And WA4DOU's equipment will not be hooked up or in service during
lightning.HA!
On Fri, 27 Aug 1999 17:03:00 GMT, Guy Olinger, K2AV wrote:
>
> I know of instances where the smaller wire (#4) was vaporized by a
> direct strike. In one case the destruction was underground, and the
> ham in question was without a ground for his tower until he was
> digging for other reasons and discovered the #4 destroyed. I am going
> to use a combination of 2-0 copper wire and copper strap for my ground
> system. Don't be cheap on the tower ground. Costs <far> less than your
> rig or house.
>
> Make sure there are no right angles or sharp turns close to the tower.
>
> On Thu, 26 Aug 1999 20:36:39 -0500, you wrote:
>
> >
> >Could some of you grounding gurus please take a look at the following
> >link and lend me some opinions? Pictured is the bottom of a 70 ft Glen
> >Martin aluminum tower with some "trial" grounding connections! I'm
> >struggling with arriving at the best physical attachment for strap
> >and/or wire to this tower. Tnx!
> >http://www.shelbynet.net/~jfleming/ground.htm
> >
> >------------------------------------------------------------------------
> >--------------------------
> >WA9ALS - John jfleming@shelbynet.net
> >Tower Project http://www.shelbynet.net/~jfleming/towerproject.htm
> >------------------------------------------------------------------------
> >--------------------------
>
> 73, Guy
> --. .-..
>
> Guy Olinger, K2AV
> k2av@qsl.net
> Apex, NC, USA
>
> --
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