I took advantage of the good weather this week to modify my 136/73kHz Tx
antenna. Looking for a few more mW
on 73.Based on the theory that more wire in the air=less
ground loss resistance,I increased the length of one of my top load legs by
20m.This involved another rope over a 60 foot oak tree, lots of bow and
arrow work
BUT instead of the modest increase in current that I expected it actually
dropped by 0.25A.
Experiance indicates that the new wire should be over "new" ground ie not
too close to existing wires,unfortunately the new wire was rather close
(about 10m at the far end) however what was more significant was that the
new wire passed directly over a dense area of Rhodedendron bushes about
10-12 feet high, so it looks like the increase in"tree loss resistance"
exceeded any reduction in ground loss due to the extra wire.
Needless to say I am back to square one ! but watch that greenery its lethal
to RF.
73 Laurie.
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