> From: owner-topband@contesting.com
To: <topband@contesting.com>
> Date: Thu, 14 Aug 97 15:52:08 +0000
Hi John,
> resonance in either the radiator in the elevated radials. And in
> the case of elevated radials there is some "magic" in not
> resonating them (contrary to what I have been saying for
> some time) per the work of K5IU. The radial system needs to
> be resonated and the radiator needs to be resonated but
> with appropriate reactive elements.
I wouldn't rethink anything without field strength measurements.
Neither current distribution nor impedance tells you a thing about
what happens in the far field, all it does is let you make a guess.
Some of the current measurements published in the past even violate
Kirchhoff's laws, indicating measurement error or stray ground paths.
The theory gets pretty thin also.
The LAST thing in the world I'd want to do is concentrate the current
and voltage in a smaller areas. Resonant radials, or especially
shortened resonant radials, concentrate the electric and magnetic
fields in small areas. This increases loss greatly. The ideal case is
where the ground system carries current that evenly and
slowly disperses over a large physical area, and has NO large
concentrated electric fields from high voltage.
It would be a lot better if everyone threw away their current meters
and impedance bridges, and used a field strength meter to reach
conclusions.
We're all likely to wind up using loaded whips for antennas...so we
can make the current "perfect". If we used four mobile whips with
very hi Q coils for radials, we'd have a perfect antenna--- as far as
current and base impedance looks. The resistance would be very low,
the current even....but I haven't the slightest doubt a FS meter
would tell us otherwise.
The best ground system is still an infinite sheet in every direction
of highly conductive material, or as close to that as we can get.
I've never seen a FS meter indicate otherwise.
73 Tom
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