Re: Tesla Ground
Subject: Re: Tesla Ground
From: richard.quick-at-slug-dot-org (Richard Quick)
Date: Wed, 5 Jul 1995 22:17:00 GMT
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> At the bottom of the foundation trench I unrolled about forty
> feet of aluminum flashing.
SR> We are having an in-ground pool installed Real Soon Now, and
SR> I had been thinking about the best way for me to use this to
SR> get a decent RF ground good for multi-kVA experimentation
SR> installed. I thought about laying down aluminum flashing
SR> like you did, but I didn't think that the current-carrying
SR> aluminum would last very long buried in the ground?
Copper is by far the preferred conductor of choice for RF
grounding. Aluminum works fine for awhile, then begins to
oxidize. This is in addition to the problems of electrolysis
when aluminum/copper connections are made without using a oxide
inhibitor. Still, my experience is that aluminum is cost
effective for the amateur coiler in RF ground applications where
the expected life span of the ground system is not much in excess
of five years, or where badly oxidized conductors can be easily
replaced. However, I do not rely on aluminum alone. My new ground
employs a significant amount of copper already, and I plan on
driving in some 8' copper pipes into the fill areas around the
property as soon as the grading is completed. But when it comes
to bang for the buck, any aluminum flashing you can throw down a
hole or trench will help.
SR> The other thing that I thought about was using the actual
SR> pool as part of the RF ground. The pool is a steel-wall pool
SR> with a heavy-duty, multi-layer epoxy coating on the steel
SR> panels, so do you think that this would be a worthwhile
SR> thing to do, or would it be a waste of time (since the metal
SR> of the pool wall would be insulated from the dirt by the
SR> epoxy coating) ... (note that I'm worrying about my planned
SR> pole-pig adventures, not the 2kVA ganged neon sign driven
SR> coils that I'm working on now).
I think that you are correct in your assumption that the epoxy
bonding would be detrimental. Since this ground installation is
intended to last for many years, maybe you could line the bottom
of the excavation with some stainless steel hardware screen
before the pool is put into place. Another thought is the use of
radials made of bare copper wire.
If you are going to move up to pole pig coils, then you are going
to need a serious RF ground one way or another. Since the heavy
equipment is going to be there anyway, you might as well take
advantage of the holes they are going to make and sink a
conductor or two into work!
... If all else fails... Throw another megavolt across it!
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