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

[Richard Fry]

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