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Topband: Shortend Vertical model questions

To: <topband@contesting.com>
Subject: Topband: Shortend Vertical model questions
From: NX4D@mpinet.net (Doug Waller)
Date: Wed, 13 Feb 2002 17:03:46 -0500
Hi Phil.........Avoid the interfering waves loss of sloping topload wires by
adding a topload above your beam.  I added a 20 ft aluminum pipe with 80 ft
of copper wire in series & zig-zagged the wire up and down 3 ft from the
pipe.  This gave me a 20 ft taller tower (80ft), which is the key to more
radiation
resistance, and increased my topload capacity immensely.  Performance
improved considerably with just same dozen radials,  & HF beam efficiency is
unchanged !  It gets full current up to the beam, plus some added radiation
from the zig-zag top load, since varying phases cancel only part of
radiation.

Resulting tower may also be used as 80m 1/2 wave vertical.  It just worked
UA9YAB on 80m.  Ant tuner is required on 80...........73/DX, om Doug / Nx4d

>The examples seemed to show that sloping top hat wires were considerably
>less efficient than with them horizontal from the top of the vertical.

> Phil Duff


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