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Re: [TCML] Using tree as RF ground

If you could connect to the rebar in your driveway, it would make about the best ground you could have. This technique is used in buildings with concrete slabs, where it is known as a Ufer ground. The advantages are: 
   -- the very large contact area
   -- the fact that concrete is a better conductor than dirt
-- the fact that the soil under the slab is wetter and therefore a good conductor 
   -- the high capacitance of the rebar network to the earth.

Here is a good article on Ufer grounds--
      http://en.wikipedia.org/wiki/Ufer_ground

---Carl
-----Original Message----- From: Dave Leddon 
Sent: Friday, October 05, 2012 5:17 PM
To: Tesla Coil Mailing List
Subject: Re: [TCML] Using tree as RF ground

I finally gave up on the tree idea.  I still think it would make a
great counterpoise (think of all of those radial tree roots) but
without any experience to back it up I'm concerned about the health
of the tree.  I've run some fairly large coils (>10kw) at the other
house out on the driveway and when power arcs connected to the tips
of tree limbs, the part stuck would die back about 4 or 5 feet from
the ends. I suspect that this was the result of localized heating. I
ended up driving the ground rod horizontally into a hillside next to
the garage.  I could tell that I pierced several tree roots along the
way, so the tree is still somewhat in the equation, but at least it's
not the sole current path to ground.
It occurred to me, as I was pounding the ground rod, that another
simple solution might be to connect to the rebar in the
driveway.  That's a lot of metal directly under the coil.
Dave
At 08:02 AM 10/5/2012, you wrote:

No that is not a good idea, If you are desperate for an RF ground try it,
but everywhere in the house there is a faucet you risk people being
shocked (especially if the line to the street is PVC) and if your pipes do
come in contact with wiring (as illegal as that is) it will destroy the
complex circuits on that breaker and if a Natural Gas line comes in
contact with your water line (as illegal as that is) it could blow up your
house! plus you could kill your water heater.

On Thu, Oct 4, 2012 at 6:33 AM, anthony lockwood <
siranthonylockwood@xxxxxxxxxxxxx> wrote:

> Hi I use my cold water tap,I dont know if it's a.good idea but It does
> work.
>
> > Date: Wed, 3 Oct 2012 21:17:29 -0400
> > To: tesla@xxxxxxxxxx
> > From: skipmalley@xxxxxxxxxxx
> > Subject: Re: [TCML] Using tree as RF ground
> >
> > Don't trust that an existing ground rod is actually in 8 feet.  I
> > have known electricians that will pound in a ground rod and then just
> > cut it off when it hits a rock and will not go in any further.
> >
> > Skip
> >
> > At 09:40 PM 9/24/2012, you wrote:
> > >I would not expect a tree to provide a sufficient ground, and plants
> > >typically do not survive high voltages.
> > >
> > >Your house has a 220V service line coming into the house.  Typically,
> there
> > >is a grounding rod driven into the ground at this location.  You
> probably
> > >you be best off driving in your dedicated ground nearby to that one. > > >As 
> > >there is one ground rod, I would expect the soil in that region to be
> > >sufficiently soft for another. Alternatively, I suppose you could > > >use 
> your
> > >house ground, however, I would advise against that as all of your
> household
> > >electronics are directly connected.
> > >
> > >Has anyone used a counterpoise as a floating ground? If so, what > > >were 
> the
> > >dimensions?  I recall reading that someone once used a twin coil as a
> > >floating ground with some success.  Effectively, just a 1/2 wave coil
> with a
> > >conventional driven 1/4 wave coil. As I recall, the "ground" lead > > >was 
> hot.
> > >
> > >Yours truly,
> > >
> > >Mike Day
> > >
> > >
> > > > From: Dave Leddon <dave@xxxxxxxxxx>
> > > > Reply-To: Tesla Coil Mailing List <tesla@xxxxxxxxxx>
> > > > Date: Mon, 24 Sep 2012 09:40:09 -0700
> > > > To: Tesla Coil Mailing List <tesla@xxxxxxxxxx>
> > > > Subject: [TCML] Using tree as RF ground
> > > >
> > > > Hi all,
> > > > I have recently moved to a new house which, as near as I can tell,
> > > > sits on top of a granite hill. I've tried pounding in an > > > > eight-foot 
> > > > ground rod at various locations only to hit impenetrable soil at a
> > > > depth of about one to two feet. The property has numerous large > > > > pine > > > > trees with diameters ranging up to 4 feet and it occurred to me > > > > that > > > > such a tree might make a great RF ground by driving a spike into > > > > the 
> > > > trunk near the base.  Does anybody have experience using trees for
> > > > grounding Tesla Coils and is there any likelihood that the current
> > > > could damage the tree?
> > > > Dave
> > > >
> > > > _______________________________________________
> > > > Tesla mailing list
> > > > Tesla@xxxxxxxxxx
> > > > http://www.pupman.com/mailman/listinfo/tesla
> > >
> > >
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> >
> > _______________________________________________
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> > http://www.pupman.com/mailman/listinfo/tesla
>
> _______________________________________________
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>



--
*Don't lower your expectations, raise the voltage !*
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