I have lots of antennas in trees (well, all mine are currently
tree-supported until the tower goes up :) )
To get the ropes up, I use a bow and arrow. Some keys to making this work
for me are to
1) weight the arrows - either wrap with fine solder and cover with
tape/heat shrink tubing, or insert some heavy wire inside the arrow.
Without weighted arrows, I left many arrows at the tops of trees :) A
fishing arrow might be better.
2) use an open-face spinning reel for the fishing line.
3) buy premium fishing line, not the cheap stuff.
I never had any luck with a slingshot- I'm not a good enough shot to get
it where I want it, and the little sinkers can't pull the line down
through thick branches.
With practice, you can stop the line and drop the arrow straight down
right after it clears the tops of the trees (90' pines in my case).
I don't bother with pulleys/etc. Just pull up nylon twine followed by
nylon rope. If a wind storm breaks something (really pretty rare- nothing
has come down in the first year at the present qth), it doesn't take long
to pull up another rope. Another big disadvantage with
pulleys/eyebolts/etc is that you will lose a significant amount of height
compared to just shooting over the top of the tree.
I feed most of these wire antennas with ladder line (cut for multiple of
1/2 wave for single-band antennas), and place a balun to go to coax at
ground level. The SWR can then be adjusted by trimming the ladderline
without having to lower the antenna. RG8-size coax is too heavy for most
tree-supported wires.
Currently trees are supporting at my qth:
all-band dipole
3 el 20m wire beam NW
2 el 20m quad NE
2 el 40m quad W
80m vertical
160m inverted L
40m dipole
Tor
N4OGW
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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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