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.
You don't say how high the trees are, but I'm guessing mature maples at 50',
maximum. What I've done at two locations now is to use insulated wire, and
simply pull it through the trees, and let the ends come down vertically.
That will get the high-current part up as high as you can. I use a bow and
arrow, and lay the hoist rope over the top of the trees.
(In VT I had 140' high white pines. Here in MD, it's a big red oak and a
tulip tree, each of which are around 80'. In each case, I don't want to
give up an inch of height, if I can help it.)
My other approach has been to use an off-center fed dipole. And I've been
using a commercial product called a "carolina windom", which forces feedline
radiation from the upper 20' of the rg8x feedline. Seems useful on the
bands. I have mine made from #12 superflex, which is easy to work with.
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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