-----Original message-----
> Today's Topics:
> 1. Re: homemade coil (Andrew Ingraham)
> ----------------------------------------------------------------------
Hello All;
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
as long as there are Hams and antennas, I have a few questions and a comment
or two.
First a question and a comment, an unkown writter makes the statement:
> > with poor reports, running 600 watts. I worked US hams at about 200
> > miles with good reports. However, I think that I can lay much of the
> > blame for the reports on the fact that I have a single radial, slightly
> > shorter than 1/4-wavelength. Once I establish a good mechanical
> > connection and a reasonable SWR, I will add radials (aiming for 60) and
Does he really mean a radial or a counterpoise?
if he really means a counterpoise, would the addition of radials really do any
good? I am under the impression that radials were not needed where a counter-
poise is used, that the counterpoise served the same perpose.
> I have no personal experience with verticals (aside from engineering at AM
> radio stations long ago), but from what I've read elsewhere, even a single
> radial is OK *as long as it is not buried* or on/close to the ground.
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.
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 ?
> Elevated above ground, it's a counterpoise, you want it to be a quarter
> wavelength long, and you need only one (though having only one might make
> the antenna a little directional). But once it's coupled to the ground, the
> soil detunes it and ground losses go way up ... unless you've got a lot of
> them.
My experience here in Tucson, Arizona has been that burying radials up to 4
inches below ground doesn't make any difference, I belive that the dry nature
of the local soil to be responsible for the low losses.
> So to improve your signal, you could either run your single radial elevated
> above ground, or bury 60 of them.
> The nice thing about buried radials, is that they can be shorter (about 0.1
> wavelength) and they don't need to be tuned.
>
> Regards,
> Andy
Yes, I fully agree, run as many radials as you can, make them as long as you
possibly
can, keep them, preferably, above ground but bury them if you must, and you will
definitely improve your signal .
To my way of thinking, the only thing that improves a good ( maybe a great )
antenna
system is a good radial and ground system.
My only other comment would be that the radials don't have to be run in a
perfectly
straight line, the wires composing your radial system can be moved around as
needed
to clear obstructions ( read that as your better halfs Roses, Mom's Petunias,
the side-
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.
O.K. thats my 2 bits worth, and should add a little more fuel to the fire, if I
have said
anything that you disagree with I am certain you will let me know and I look
forward
to hearing it.
73 de kc7vda (Dan)
>
>
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> End of Antennaware Digest, Vol 44, Issue 1
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