Hi Tom, Thanks for the I/P yes N6RK has interesting info on his web page
about the work he did measuring radial field differences all very
interesting stuff. It can be found at <http://www.karlquist.com> . 73 Clive
GM3POI
-----Original Message-----
From: Tom Rauch <w8ji@contesting.com>
To: TowerTalk <towertalk@contesting.com>; Clive Penna
<clive@gm3poi.prestel.co.uk>
To: <towertalk@contesting.com>
Date: 30 March 1999 12:48
Subject: Re: [TowerTalk] Ground Radial Fields
> HI, Does anyone have any field strength data, re the lowering
> of radiation angle in a given direction if extra radials are concentrated
> in that direction. ie taken to the extreme 60 radials covering 180deg
> whether that arrangement would have the performance of 120 radials at the
> mid way point,and the radiation angle increasing as you run out of
> radials. 73 Clive GM3POI
You might ask on rec.radio.amateur.antenna I think it is N6RK who
actually measured this stuff, and his measurenents agree with
theory.
Theory tells us the radials do nothing at all for low wave angle
performance unless they are several wavelengths long and very
desnse (about .05 wl spacing) at the open ends.
Also, if you concentrate radials in one hemisphere efficiency in
EVERY direction drops.
I found that true at WAAM radio, where someone cut and removed
all radials going in the direction of a desired null. The only result of
that was a decrease in field strength in all directions and instability
of the array with soil moisture changes.
73, Tom W8JI
w8ji@contesting.com
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