Rick (W-A-one-R-K-T) wrote:
OK, per the thread on "Question on grounding rods", I'm supposed to use
8-foot grounding rods rather than twice as many 4-foot rods. I can see
that.

But, we're built on a ledge, one big wide rock that stretches from the
seacoast to the Vermont state line (that's why they call New Hampshire the
"Granite State"). I can get three feet depth at best before running into
solid rock. An electrician friend of mine says I can drive the ground rod
in at a 45-degree angle, but that would still run an 8-foot ground rod to
a depth of more than 5.5 feet below the surface.

Can't be done.

So, what do I do next?

======================================
Don't know your private land situation , but instead of the
'prescribed' 8ft rods you can obtain an excellent rf earthing system by
covering an area with 'galvanised chicken wire mesh 'pegging the mesh to
1 or more short rods or stainless steel pins as used for the BBQ

If you have a grass lawn in your garden cover an area ,the larger the
better, with the above mesh. Within a few weeks ,if not earlier ,the
grass will make the mesh invisible and you will be able to apply a
lawnmower over the mesh to cut the grass.

Ensure the mesh is well connected to a rod via a jubilee clip which also
connected to the shortest possible length of insulated ,thick wire to
the shack. The jubilee clip with mesh and wire connected should be
protected against corrosion by means of self-amalgamating tape

The wire mesh is also a good alternative to multiple radials when using
a vertical antenna

I remember the situation with a Butternut vertical antenna which
initially only had 1 ground spike ,but when surrounded by wire mesh
,signal reports improved by 1 to 2 S-points.


Frank GM0CSZ / KN6WH

"Rick (W-A-one-R-K-T)" wrote in message
news

OK, per the thread on "Question on grounding rods", I'm supposed to use
8-foot grounding rods rather than twice as many 4-foot rods. I can see
that.

But, we're built on a ledge, one big wide rock that stretches from the
seacoast to the Vermont state line (that's why they call New Hampshire the
"Granite State"). I can get three feet depth at best before running into
solid rock. An electrician friend of mine says I can drive the ground rod
in at a 45-degree angle, but that would still run an 8-foot ground rod to
a depth of more than 5.5 feet below the surface.

Can't be done.

So, what do I do next?


ok, the answer is:

first, you get your electrician friend to install or update your grounding
to meet the building code. that, by definition, takes care of electrical
safety grounding.

Second, you ask him this: "if i install an antenna (tell him tv antenna on
a tower), how do i ground the tower, and how do i connect it to the existing
ground". do what he says right outside your shack and consider that your
lightning/rf ground improvement, this is where you connect your single point
(equipotential as some people like the big term) ground for the shack
entrance.

NOTE: VERY IMPORTANT! any ground you do for lighting protection for
antennas or for rf MUST be connected PROPERLY to your house power ground...
this is not done through the 3rd prong on your power cords. nor is it done
through a cold water pipe, nor a piece of 14ga wire wrapped around the
ground rod.

Third, if you put up a vertical or some other antenna requiring a ground
screen to reduce losses that must also be connected the same way to your
power ground. the shield of the coax is NOT sufficient.

Rick (W-A-one-R-K-T) wrote:
OK, per the thread on "Question on grounding rods", I'm supposed to use
8-foot grounding rods rather than twice as many 4-foot rods. I can see
that.

But, we're built on a ledge, one big wide rock that stretches from the
seacoast to the Vermont state line (that's why they call New Hampshire the
"Granite State"). I can get three feet depth at best before running into
solid rock. An electrician friend of mine says I can drive the ground rod
in at a 45-degree angle, but that would still run an 8-foot ground rod to
a depth of more than 5.5 feet below the surface.

Can't be done.

So, what do I do next?

I assume you're subject to the National Electrical Code in some version
or another?

What do you do? You use a Concrete Encased Grounding Electrode

Dig trench, lay wire, fill with concrete, done.

(The NEC also allows you to dig trench, lay your 8 foot rod sideways in
the trench, and then backfill.. but the CEGE is a better ground)

On Thu, 12 Jul 2007 20:18:34 -0400, "Rick (W-A-one-R-K-T)"
wrote:


OK, per the thread on "Question on grounding rods", I'm supposed to use
8-foot grounding rods rather than twice as many 4-foot rods. I can see
that.

But, we're built on a ledge, one big wide rock that stretches from the
seacoast to the Vermont state line (that's why they call New Hampshire the
"Granite State"). I can get three feet depth at best before running into
solid rock. An electrician friend of mine says I can drive the ground rod
in at a 45-degree angle, but that would still run an 8-foot ground rod to
a depth of more than 5.5 feet below the surface.

Can't be done.

So, what do I do next?

At 2300 feet up a big hunk of granite in southern VT, we have only
about 1 foot of surface soil, below which it is all low grade granite.
The house was constructed with a Ufer grounding system. Out at the
tower, we installed a system of radial wires from the tower base to
get whatever ground we could.

All of the antennas here are balanced, and we get out quite well on
all bands. The antennas think they are a thousand feet up, and I
have good directionality even out of the 40 meter beam when the crank
up is fully retracted. Raising the tower is only needed for getting
the above the surrounding trees.

One of the things that I observe as a result of living/operating from
a high ground resistance location is that it seems that we seldom get
nearby lightning ground strokes. They seem to hit down in the valley
where the soil is more conductive.