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Re: [TowerTalk] Speaking of wire mesh...

To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Subject: Re: [TowerTalk] Speaking of wire mesh...
From: jimlux <jimlux@earthlink.net>
Reply-to: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Date: Sun, 17 Jan 2010 12:50:53 -0800
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
jimlux wrote:
> 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.
>>

Looking over Laport (since it was just mentioned)

"...Meshes of crossed wires, which were once widely used, should not be 
used with vertical radiators, because the return paths are not direct 
and eddy-current losses in the closed loop circuits of the mesh can be 
appreciable."

Page 121

I'm still thinking about how the magnetic field (which is mostly 
"around" the vertical radiator) would couple to the loops in the mesh. 
That is, the field doesn't have a huge amount of curl, when sliced in 
the horizontal plane.
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