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Re: Topband: Ground mounted 1/2 and 1/4 wave verticals (was GAP)

To: <topband@contesting.com>
Subject: Re: Topband: Ground mounted 1/2 and 1/4 wave verticals (was GAP)
From: "Richard Fry" <rfry@adams.net>
Reply-to: Richard Fry <rfry@adams.net>
Date: Tue, 18 Dec 2012 04:48:45 -0600
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Don k4kyv wrote:
I would be interested in looking at any actual experimental data compiled to quantify ground losses, using physical antennas fed with physical rf watts with data collected using a variety of physical ground planes.

In 1937, Brown, Lewis and Epstein of RCA Labs published a benchmark experimental study of this in the Proceedings of the IRE - still covered by copyright. But clips from it have been available on line for a long time.

The NEC4 study linked below shows the affect of earth conductivity on the system radiation efficiency of an electrically short monopole on 160m, using 32 x 10m buried radials. The fields radiated by this system range from 6.8 dB to 9 dB below those of that monopole on that frequency using the same applied power, and having no losses in the loading coil or r-f ground connection.

http://i62.photobucket.com/albums/h85/rfry-100/10m_Vert32Buried_Radials.jpg

RF
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It is undesirable to believe a proposition when there is no ground whatsoever for 
supposing it is true. &#8212; Bertrand Russell

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