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Re: Topband: Monopole Elev Pattern w.r.t. Earth Conductivity

To: <topband@contesting.com>
Subject: Re: Topband: Monopole Elev Pattern w.r.t. Earth Conductivity
From: "Richard Fry" <rfry@adams.net>
Reply-to: Richard Fry <rfry@adams.net>
Date: Wed, 24 Oct 2012 18:33:27 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>
The tall vertical tower was definitely worse compared to shorter verticals,
and had almost no short skip signal around Georgia. I had isolation chokes
for lights and a base insulator, but that 300+ foot tower was so poor I
never used it as a vertical.

Not sure what frequency this comment applies to.  But a 300-ft tower would
be about 197 degrees in physical height on 160m, and its elevation pattern
would be close to the pattern for the 195-degree monopole shown in the plots
linked below.

The short skip being sought might better have been provided by a shorter
monopole, but a longer monopole (up to 5/8WL) would provide better
groundwave fields and low-angle fields, even with the ~poor earth conductivities
in some parts of Georgia.

http://i62.photobucket.com/albums/h85/rfry-100/MWElPatComparison.jpg

R. Fry
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