I read with interest the web site comments on grounds for 160M. Those
with limited space for a ground system or who cannot bury wires should
not despair of operating on 160M.
As S92SS in Sao Tome I had a very small yard, much of which was under
concrete. After much hounding by the 160 meter crowd I gave it a try
and was successful in making many hundreds of contacts all around the
globe using around 350 watts and an antenna that most topbanders would
find laughable. The 1/4 wavelength radiator had only about a 35'
vertical run from the 6 1/2' high feed point and then took off in
various directions horizontally and vertically to make up the resonant
length. The ground system was only four 55' long wires bent to fit and
elevated on the average no more than 8'!! These were tied together and
resonated as a system with an inductor. The feed was isolated with a
common mode choke, so this four wire system was definitely the only
directly connected ground reference. I had access to a commercial
Potomac Instruments calibrated field intensity meter receiver and was
able to make meaningful measurements at a distance. I don't recall
the actual figures, but I found the signal strength at one kilometer
to be respectable under the circumstances when compared with estimates
of what a 90 degree commercial broadcast style antenna should have
given.
I must admit that one major advantage I had over the average topbander
was L O C A T I O N!
Charles Lewis
ex S92SS & A22AA
Now SV0LM in NE Greece
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