> From: email@example.com (Guy Olinger, K2AV)
> Subject: Re: [TowerTalk] Ground Radial Fields
> Is it possible that on N6RK's figures, that his comparisons were
> invalidated for a setup using equal radials over 360 degrees, simply
> because he did not run them in all directions?
> This also leaves one with the enormous problem of huge real estate and
> a fortune in wire to validate.
> I also would appreciate some comment as to whether 20m results
> properly extrapolate to say, 160m. I'm not planning to use a vertical
> on 20m, though I understand why he used 20m.
> Guy Olinger, K2AV
I'm not sure if this is clear on my web site, but I had 32 quarter
wave radials spaced equally around the test vertical in addition to
the 60 radials that were 4 wavelengths long. So my opinion is that
the vertical should have been in good shape as far as a counterpoise
is concerned. The 4 wavelength radials should have been necessary
to reduce the Brewster angle only in the direction of propagation.
Certainly, DXpeditions on the proverbial desert island get excellent
use of sea water in one direction only, as explained many times by
N6BT. The problem is that you can't put out enough wire to
duplicate the ocean.
My original motivation was to see if a 160 meter ground radial field
of 120 half wave radials that I was going to build anyway
would do anything magic on 20 meters, if the density were increased.
When my initial experiments with 60 radials over a 45 degree angle
produced 3 dB gain at the most, I decided this thing wasn't worth the
effort, so I didn't put in the other 400+. It was enough work to
put in 60 of them. BTW, they were on the average about 6 inches
above the ground because weeds held them up.
I agree that you cannot be sure that results would extrapolate to
160 meters, but on 20 meters, this monstrosity took up 5 acres as
it was, and on 160 it would take up 320 acres, challenging even
land barons such as W8JI :-) to find space for it, so it is probably
of academic interest only. Also, it should be noted that it was
installed in an area of supposedly high ground conductivity, so the
radials might have helped more in the desert.
Rick Karlquist N6RK
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