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Re: [TowerTalk] dipole question

To: "Al Williams" <alwilliams@olywa.net>, <TOWERTALK@contesting.com>
Subject: Re: [TowerTalk] dipole question
From: "Tom Rauch" <w8ji@contesting.com>
Reply-to: Tom Rauch <w8ji@contesting.com>
Date: Fri, 22 Jul 2005 23:59:37 -0400
List-post: <mailto:towertalk@contesting.com>
> 2. The current flowing on the outside of the shield must
have an opposite
> current (charge) flowing somewhere.  Is it the portion of
the antenna that
> is connected to the center conductor.

It can be in either or both halves of the antenna.

> 1. If for example, 100 watts is output but 10 watts is
diverted to the
> outside, that still leaves 90 watts to the intended
antenna--an
> insignificant (?) loss.

Power division might be difficult to measure or determine.
Antennas radiate by ampere feet (but of course phase has to
be considered). Radiation from a feedline can be
significant.

The bad thing about common mode feedline currents on
transmitting is the RF in the shack and pattern distortion.

An even worse thing is on receiving the feedline and
everything attached to it, including the power line and all
the noise generating stuff attached to it, is part of the
receiving system.

73 Tom

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