I use tree supported wire antennas, almost exclusively for the 14 years
I have lived at the present QTH. Here are a few hints worth considering:
Getting someone to climb a tree to get the line over the right branch
may be superior to using a sling shot or cross bow, or cast with a
fishing rod, because you can get the line exactly where you want it that
way. If you can get it right by launching it up there somehow, then good
for you. I'm using stainless steel eye bolts screwed into my trees. You
cannot install those with a crossbow. Palm tree "branches" don't last
long enough. A line over a stout branch will work fine for many kinds of
trees.
Whichever way you get the line up there, do not use that line directly
to hoist the antenna. Use that line to hold up the block (pulley)
through which the antenna support line runs. This makes adjustments,
reconfiguration and repairs much easier. In fact it may be the
difference between repairs being possible, and having to start all over.
It also reduces or eliminates rubbing of the line on the tree. A good
thing to reduce since that can damage the tree and the line.
Sadly, the junk at the two large hardware chains available to most of
us is likely not of the same quality as that used in the aircraft
industry.
Or the marine industry. DO NOT use hardware store pulleys. Even the best
ones are not very good. Use small sailboat pulleys. If there is a
boating supply store around, check out what they have. Otherwise order
something on line. I have purchased mine from Westmarine. There may be
other boating supply stores on line, that is the one I know. I'm not
intending to promote them.
Use line that is the appropriate size for the job and pulleys the
appropriate size for the line. Even the best pulley can jam if the line
you run through is too big or too small.
The line that runs through the pulley should be a continuous loop so
that if you accidentally let go of it it cannot un-thread from the
pulley. You could put weights at each end of the line, which are too big
to go through the pulley as an alternate method to prevent letting the
line fall out of the pulley. I find the loop method to work fine.
I have not found a need for bungees or weights on my lines. I just tie
them so that the antenna wire has a reasonable tension, but not too
much. If the trees at opposite ends are moving in the wind, and are not
in exact sync, it is not a problem. I haven't had an antenna break due
to that cause yet. This is no doubt highly dependent on the variety of
trees you are using. I have tall skinny palm trees. If you have a need
for a weight or a bungee, have it down near the ground where you can
tend to it.
When the antenna wire does break, or has something hanging from it that
you want to remove, you will be really glad you used a line through a
pulley. Mine usually collect palm fronds. (Probably because I am using
palm trees) I am amazed at how seldom the palm fronds break my wire.
They usually just hang there. I am using something like 28 AWG enameled
wire. I could use heavier wire, and require more tension to hold it up
as nicely. The small stuff works great for me.
Have fun, be safe. If you plan ahead it will last longer and you'll have
less frustration.
DE N6KB
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