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Re: Topband: Tuning elevated radials

To: <topband@contesting.com>, "Phil & Ann Duff" <na4m@arrl.net>
Subject: Re: Topband: Tuning elevated radials
From: "Tom Rauch" <w8ji@contesting.com>
Reply-to: Tom Rauch <w8ji@contesting.com>
Date: Sat, 17 Sep 2005 17:47:02 -0400
List-post: <mailto:topband@contesting.com>
> I think his paper and references seem to address radial
current
> imbalances with regard to vertical antenna patterns with
no mention
> how it relates to losses.   Dick did make radial current
measurements
> with different length radials, etc. but again.. I think
not in
> relation to losses

The fact remains unequal currents in equal length radials
proves each radial is located in a greatly varied electrical
environment. Perhaps the radials are at differing electrical
heights because of soil conditions below the radial, perhaps
some radials are near other unintentional re-radiators, or
perhaps the earth below some radials is substantially
different in loss than earth under other radials.

If we balance currents when radial surroundings have been
proven to be unequal, equal currents will guarantee some
radials will radiate more than others!

I know it is a matter of how much distortion in pattern we
can notice or accept. I'm just pointing out making currents
perfectly balanced will not cancel farfield radiation when
the media around each radial is different. If the media is
the same, you would not need to do anything because current
would all be equal. The only thing differing currents prove
is we need differing currents to balance the system in the
far field.

It's a circular theory. The problem creating the need for a
fix (an unbalanced media) indicates the equal current fix
won't work as planned! It does however create another
logical reason to make a radial system smaller, more lossy,
and more critical.

73 Tom

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