I suppose that one could make some sort of impedance bridge measurement to
measure the impedance between your "ground connection" and some standardized
electrode, for which the characteristics can be known by calculation. Like,
for instance, a big sphere, or maybe a flat plate, or a single wire suspended
at a fixed height above the ground.
Ground resistance/impedance measurements are one of the ways used for
subsurface exploration, so there should be some technical literature available.
Once one knows what the "electromagnetic structure" of the soil is, then you
could use any of a variety of modeling techniques to see how close your scheme
comes to "ideal".
This comes down to "what is ground"? A non-trivial question that really can
only be answered, it depends....
kelly johnson wrote:
>
> So, how do you know if you have a good ground
> or not? If there's stray RF all over the place
> I usually assume there's a bad ground, but unless
> it's really obvious like this, how do you tell?
>
> On Wed, 10 April 2002, "Jim Lux" wrote
>
> >
> > Nope.. I haven't tried it for RF (got a standard
> ground rod hammered into
> > the ground).. My house's electrical service, though,
> does use a UFER ground.
> > A bit of web searching should turn up some info on RF
> properties though..
> > Lightning protection and RF are very similar
> applications...
> >
> > I was more interested in pointing out that the
> surface area of a ground rod
> > isn't all that huge... so a buried 2x2 foot copper
> plate could actually be a
> > "better" ground...
> >
> > A lot also depends on where your water table is, how
> wet the soil is,
> > capacitive coupling, etc.
> >
> >
> > ----- Original Message -----
> > From: "Bill Axelrod" <bill@axelrods.org>
> > To: <jimlux@earthlink.net>
> > Sent: Wednesday, April 10, 2002 8:32 PM
> > Subject: Re: [Towertalk] Grounds, UFER grounds
> >
> >
> > > This is an interesting thread since one of my goals
> this spring is to
> > > install a better system ground. Jim, if I read
> your posting correctly,
> > you
> > > say that I would be essentially equally served with
> a 10x10 inch plate
> > than
> > > I would with a 1/2" diameter rod 10 feet long.
> > >
> > > Does that pertain to the RF ground as well as the
> DC ground? If you use
> > > such a ground, how have you fared with it?
> > >
> > > Thanks and 73... Bill K3WA bill@axelrods.org
> >
> >
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>
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