[Antennaware] radials

Andrew Ingraham ingraham.ma.ultranet at rcn.com
Thu May 10 18:02:02 EDT 2007


> If you will pardon a newcomer ( to your group) for poking his " beazer" into
> what appears to be an ongoing argument, an argument that I am sure will continue

Actually, there wasn't any argument.  Just some questions and answers (in
March), and my additional recent comments.

> Does he really mean a radial or a counterpoise?

As I say, I'm not a 'verticals' guy, so I don't necessarily know the proper
nomenclature.  But I thought he meant the wire was buried, which I think
makes it count as a radial, even though there was only one and radials
usually implies several, in a mostly radial pattern emanating from the base.

I suppose one could say that a radial system is one form of counterpoise.
It is where the other part of the current at the base of the tower goes.

> I too have served my time working with AM stations, the vertical of my station
> was surrounded by 160 radials that, after the first few feet, were burried under
> egg sized rocks.

Around here, they are either in moist soil, or (more commonly) in wetlands.
My last AM station was in a marsh.  At high tide I think the radials
were submerged.

> However,when working with Ham Band verticals, I have been under the
> impression that a minimum of 4 radial, each 1/4 wave length of the lowest
> frequency to be used was a necessity. ( and yes, I understand that more is
> usually better, up to a certain point, ) Am I wrong about the length or does it
> matter ?

Well, from what I've read elsewhere, burying them (in soil) detunes them so
much that length hardly makes any difference; they just need to be more than
about 1/10 wavelength long to be effective.  The current couples into the
conductive soil, ground water, etc.

If the soil is very dry/rocky, maybe length is more important.

> walk or Juniors swing set, sandbox etcettra) . If that obsticle is a beautiful yard full of
> grass that you are understandably reluctant to dig up, the solution is to beg, borrow or
> otherwise scrounge a side walk trimmer. With it you can easily make very nice, narrow,
> cuts in the grass, without any dirt being thrown up on the grass.  You then simply stuff
> the radial wire into the cut you just made and when you next  water the grass the cuts
> will  disappear.

I've read that some people just lay the wire on the ground, maybe stapled
down to hold it in place, and after a few mows you can't tell that it's
there anymore.

Andy




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