On Sun, 28 Nov 2004 15:20:37 -0800, Bill Turner
wrote:
On Sun, 28 Nov 2004 21:15:13 GMT, Gary Schafer
wrote:
It's kind of difficult to get a resonant quarter wave into a back stay
as you don't usually know where ground is. Ground can be any number of
feet from where the feed point is on a boat. Every thing above real
ground is antenna.
_________________________________________________ ________
Correct. For simplicity, figure the feed point is right where the coax
shield connects to the ground plane. As you said, everything above that
is antenna. On a fiberglass sailboat, the hull is quite transparent to
RF on HF frequencies, so the presence of a few feet of antenna inside
the hull is of no consequence.
When I said "you don't usually know where ground is" I meant that on a
boat what may look like real ground may not be. Usually there are a
lot of different things tied together to try and get a decent ground
for the radio. The length of those leads are a factor. There is no way
to know for sure how long the actual ground lead is without measuring
where your antenna resonates.
Cut and try with a backstay is not practical.
73
Gary K4FMX
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