The small square image on the web site you pointed to looks like
a split ground wire bolt. I have not seen them as galvanized before
but they are readily available in several sizes in brass in the electrical
departments of places like Home Depot and Lowes. I suppose it
is the "No image" pieces you were really pointed at.
Several years ago I used galvanized chicken wire mesh radials during
the winter months so they just sat atop the ground. They seemed to
improve operation but I didn't do any scientific study. The mesh I had
was about 24 inches (60cm) wide. I used aluminum strips with several
bolts and Noalox at the antenna end of the mesh. I just rolled up the
mesh in the Spring,
73, Larry W6NWS
----- Original Message -----
From: "Ian White GM3SEK" <gm3sek@ifwtech.co.uk>
To: <towertalk@contesting.com>
Sent: Friday, September 23, 2011 3:53 AM
Subject: Re: [TowerTalk] low band antenna without good ground
> Alex K2BB wrote:
>>I cannot add more wire radials - there are 3 radials already each way
>>from the tower, 3 feet apart.
>
> With so little ground area, you'll need to try much harder than that -
> but believe me, it WILL be worth it.
>
>>I remember reading about some aluminum "chicken mesh" used as radials.
>>I think it might help. Where do I get it?
>>
>
> Broad strips of radial material will definitely be better. Probably the
> key reference is still the article by Robert Sherwood (yes, *that* Rob
> Sherwood) in Ham Radio, May 1977.
>
> But don't use chicken mesh of any kind! It's great for expeditions and
> Field Days but in a permanent installation it will break up in the
> ground (a former owner of this house had kindly left some test samples)
> and will be a nightmare to remove.
>
> I'm having much better experience with heavyweight galvanized "stock
> fencing", about 3ft wide and divided into 6in squares which are plenty
> dense enough for HF. This is much stronger and more heavily plated than
> chicken mesh, and surprisingly it was also cheaper.
>
> Although galvanized steel cannot equal traditional copper wire for
> conductivity, the losses are more than offset by the greater ground
> coverage. (Remember also that the skin effect concentrates the RF
> currents into the more conductive zinc plating; and because it's a mesh,
> the current density in the individual wires is quite low.)
>
> For connecting the strips of fencing together at the base of the
> antenna, these 4-way clamps proved to be ideal (sorry, there seems to be
> either no image or the wrong image for this product):
> <http://www.rappa.co.uk/products/151-four-way-line-clamp-25-pack>
>
> There's sure to be something similar at your neighborhood NYC farmer's
> store.
>
>
> --
>
> 73 from Ian GM3SEK
> http://www.ifwtech.co.uk/g3sek
> _______________________________________________
>
>
>
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