When placed on, or below, dirt galvanized wire rusts away pretty fast here
in Louisiana. After a year or two I wouldn't want to be depending on it for
anything important. Using copper wire might seem more expensive, but when
everything is considered I doubt that it would be.
------------------ Wes Attaway (N5WA) ------------------
1138 Waters Edge Circle - Shreveport, LA 71106
318-797-4972 (office) - 318-393-3289 (cell)
Computer Consulting and Forensics
-------------- EnCase Certified Examiner ---------------
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of jimlux
Sent: Sunday, January 17, 2010 2:13 PM
To: Tower and HF antenna construction topics.
Cc: n4zr@contesting.com
Subject: Re: [TowerTalk] Speaking of wire mesh...
K1TTT wrote:
> They may not be perfect, but they do help. I use that stuff under my 80m
> 4-square... even with the radials raised up 10' putting 150' of that stuff
> under each vertical was still a measurable change to the impedance when I
> was putting up the first one and testing it. I got it in 100' sections
from
> a local fence installer and put 100' out from the center of the 4-square
as
> far as it went past each vertical, then a 50' piece at 90 degrees to it
> crossing at the base of each vertical. A 1/8" galvanized cable clamp does
a
> good job of clamping without need for matching metals if you use
galvanized
> wire, then use a bigger galvanized clamp to attach to the tower rung.
>
>
The question I would have is whether you'd be better spending money on
copper wire for radials than spending it on steel mesh. Obviously, if
one has a cheap source for either, than that might push you one way or
the other.
For tesla coils, which are entirely a near field thing (100-200 kHz),
mesh works great, but there, it's because the mesh makes a more uniform
electrostatic field.. the advantage is in the field shape more than the
loss effects. The mesh is basically one plate of a capacitor.
But for antennas, I'm not so sure.
However, it occurs to me that this is something that NEC4 can model
(albeit tediously), except for the permeability of the wires.
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