I've always identified an interconnected mesh, regardless of what metal
it's mad of as a counterpoise. It may, or may not be "tuned".
Radials are generally identified as being of specific lengths generally
1/4 wavelength to provide the other half to the vertical 1/4 wave in
question, or the the part that make it a vertical dipole. As the radials
may be either one the ground, or elevated, provides a more manageable
match to the antenna system.
I'm sure have stated this, I will have to don my asbestos underwear.
Conceptually, since my teens I have understood it this way.
73
Chuck, W6AJW
On 10/27/2016 10:10 AM, Kevin Kidd wrote:
Mike,
If it's not copper or some alloy thereof, don't waste your time for a
permanent installation. Unless it is in a desert region, it's useful life
could probably be measured in months. I have and can get copper expanded
mesh but we no longer use it very much in broadcast. We typically build an
AM ground system using 120ea 1/4wave radials and 120ea 50ft radials to
concentrate as much copper around the tower base as possible. We do
sometimes use the copper mesh on top of large concrete pads for self
supporting towers.
The expanded copper mesh comes in rolls that are 8x24ft and now sells for
about $500/roll. It wasn't many years ago that I was paying about $150 per
roll but sources have dried up and the cost has gone out the roof.
Ironically, I am working on an AM broadcast tower right now where someone
had the great idea of putting down either stucco mesh or something
similar. It doesn't look like rabbit or chicken wire. It has been in the
ground a number of years but you can literally pull it up in pieces with
your bare hand. This, as well as their attempts at bonding obviously
failed many, many years ago.
Regards,
Kevin C. Kidd, CSRE/AMD
Lawrenceburg, TN
AM Ground Systems Company - WD4RAT
kkidd@kkbc.com -- 866-22-RADIO -- 866-227-2346
www.amgroundsystems.com
On Wed, Oct 26, 2016 at 8:36 PM, W0MU Mike Fatchett <w0mu@w0mu.com> wrote:
I just poured the base for a self supporting 80m full sized vertical. The
manual recommends individual radial wires and to make sure they never
overlap as that can cause issues.
My question. I have a bunch of what I think is stucco mesh. I was
thinking about laying down around the base of the vertical or laying out in
a couple of direction assuming I can get a decent bond from one piece to
the next.
Is there an issue with using this mesh? Would I just be better off
running single radial wires versus having a dense field around the base or
do both and hook up the separate radials to the end of the mesh in a
circular fashion.
I just don't want to waste my time of folks don't think the mesh is worth
fooling around with.
Thanks for the comments.
Mike W0MU
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