I have been watching this thread for some time and hope you do not mind if I
add my thoughts. This seems a good time to comment.
I'm not at all sure what the electicity service is in the USA but I guess
that there may be other nationals on this list.
Here in Guernsey we have a mains service similar to the UK. It is now
common for mains feeds into properties to have all earths bonded together
with other properties, in the near vicinity, on the heavy duty screening
cable for the main feed. This screen is bonded to earth potential at the
power station some miles away. In this approach, there is a serious risk to
the amateur who then earths his station via a ground stake.
There is an excellent article on this topic, written some years ago in the
RSGB journal, called "The killing fields"
Under normal circumstances, nothing happens. If however, the bond between a
nearby property is accidently severed, then it is highly probable that the
only path to earth for the properties still linked is via the amateur's
earth stake, with disasterous consequences.
Here at my various QTH's the bond to the sleeve has always been removed and
a new ground stake is inserted as the only earth for my property. My radio
earth consists of a number (20) of short stainless steel rods connected
together with stainless steel wire.
On other points raised, apart from the more obvious ones of water ingress
and physical damage, there is good advice given about never placing a ground
stake into the concrete base of a tower. A direct lightening strike is said
to be likely to shatter the base into fragments by rapidly and violently
boiling off any moisture. This may also hold true for basements. It has
also been argued that most lightening protectors don't protect.
Finally, is not a lightening conductor a lightening repeller?
Not being an expert, I trust that you will accept my comments in good faith.
Hi!
With very best wishes for the Season.
73 de Mike
----- Original Message -----
From: <ac5e@comcast.net>
To: <tentec@contesting.com>
Sent: Thursday, December 11, 2003 4:07 PM
Subject: Re: [TenTec] Lightning, RF and Grounding [WAS - PS grounding]
> While we are on the subject of lightning, let me mention a friend. I went
to school with Scott Bradley, more years ago than I care to contemplate.
While I went to learn about electronics, Scotty decided to make some money
on the wheat thrashing circuit.
>
> Scott was found dead after one of those dry prairie thunderstorms you get
in the Dakotas, lying by his truck a few feet from a windmill tower. He
thought the tower would act as a lightning rod, and it would be safe enough
to step out and take care of a little urgent business. Lightning hit the
tower, and the induction field paralyzed his heart nerves.
>
> Since then many hikers and campers have been found "mysteriously dead"
near lightning blasted trees. Death by induced electromagnetic field is a
recognized "act of God." And that is cause for thought for those of us who
put up Rohn or other makes of "neighborhood lightning rods."
>
> YOU DO NOT want to be within fifty feet of a lightning strike under any
circumstances. If it is at all possible locate your tower as far from your
house/shack/occupied building as it is humanly possible. Do provide an
adequate and preferably redundant ground for the tower, and for any cabling
to and from the tower. This is one case where more is not only better, the
best you can do is not enough.
>
> 73 Pete Allen AC5E
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>
>
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