That's a slightly different animal. It is acts essentually like a dipole
which is a balanced antenna. Balanced antennas do not need a
ground plane. Standoffs are not needed because the mast is part of
the ground side of the antenna which is what the shield on the coax
is. I experimentd with a real dipole by stretching it between the masthead
and the radar arch. It was fed in the middle with a balun. Worked well, but
keeping the feedline out of harms way proved to be a problem.
If the antenna in question was fed with coax, a balun would be
desirable.
Doug, k3qt
s/v Callista
"Gordon Wedman" wrote in message
news:6wAEd.61994$nN6.13173@edtnps84...
Over the holidays I killed some time looking through a few back issues of
Cruising World. In the April 1986 issue a boat-based ham operator said he
used a top-fed backstay antenna with excellent results AND he had no
in-hull ground plane. He said he connected the shield from his feed wire
to the mast-side of the backstay and this allowed the mast and all the
standing rigging to act as a ground plane. He didn't say anything about
using stand-offs between the feed wire and the mast. I would think you
would get a lot of signal loss over that much length if you didn't use
stand-offs?
If a person could put up with the appearance and make sure the whole
set-up didn't get torn down by sails/running rigging, would this really
give good performance? I don't recall reading about this type of set-up
so I guess its not too common on recreational boats but maybe it could be
worth considering in some situations?
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