On the CQ-Contest Reflector K7QQ said: "You have to keep in mind that the best
antenna doesn't exist. You can only get up what you can and it is never
enough." Well that's where I am, but I'd like advice from you experts on how
to improve my antenna, within my personal constraints.
My antenna is a dipole, about 99-ft long, strung between maple trees of the
neighbors on either side. (It's already much higher than the peak of my roof.
No other supports available.) The feed line is mostly window-pane twin lead,
with several feet of coax to get into the house and reach the Transmatch.
Yeah, I know it's not balanced; but should I really care, as long as the RF
goes somewhere other than losses? (And I know that the high SWR might cause
the coax to arc over or have noticeable resistive loss, but that's one of the
constraints -- for now.) My main operating interest is SS CW, with a little
other casual contesting (work the Club members and the big guns) and a bit of
40M CW DXing (if I can get the antenna to work better).
I've pulled the ends of the dipole as far as I can into the trees (maybe too
far), but it still sags quite a bit -- 5 to 10 feet, by eye. Some of the sag
is probably from the weight of the antenna wire and the feedline, but I think a
lot of it is simply from the dipole's being longer than the span between the
trees.
I have two seat-of-the-pants concerns. First, I may be getting losses from
having the ends of the dipole in the foliage. Second, the vertical-V might be
more NVIS-like than Iis good for me. Obvious solution is to shorten the dipole
a bit, but that would make it even shorter than the recommended 100-ft minimum.
So, first question for the experts: Do you think I'll do better to shorten
it, or should I leave the ends in the trees?
Second-order solution and question: If it turns out that the feed line is
weighing down the center, would I be better off to let it sag than to change to
something more like TV twin-lead? (I recall some discussion here about Radio
Shack selling a twin-lead with heavier-than-typical conductors.)
Thanks for your help.
73, Art K3KU
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