Original article from: Wayne Sarosi
Reposted by Rob Dennis,Moderator HAM_TECH,for use of the FIDO HAM_TECH echo.
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SUBJECT: Tower Series,part 3
TREES:
Trees have been used as antenna supports for years.
There are some problems though. Trees grow,they have leaves or needles,they
sway and are probably the greatest target for lightning than any man made
device.
I have used trees for an antenna support many times. In my CB days,I cut the
top off an oak tree in Connecticut,35 feet up,and used chimney straps to hold
a mast for a 'Starduster' quarter wave antenna.
Here in Florida, I use a palm and a sycamore for a DX-A (40,80,& 160) and
he
same sycamore and a small maple for my 40 IVee. Both are fed from my tower.
I have a pulley system to raise the antenna I need for specific operations.
* sycamore
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* palm
* maple
<--------North
Trees must be cared for when attaching support lines. Too tight and you can
strangle the branch or worse, the tree.
Never use a dead tree. They're an accident in the making.
Beams in trees are not a good idea. Getting them up there is a pain in the
butt to say the least save a crane. Constant upward growth interferes with
he
pattern and the ability to turn them thus requiring pruning.
Pray you don't have a problem like bad SWR,bent elements,or a water soaked
trap.
I would suggest keeping trees for verticals or tie off points.
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WOODEN TOWERS:
These can be interesting. They are heavy,can rot,and don't stand much for
he
weather.
Wooden towers are subject to many enemies such as bugs,birds,and rain.
The sun can dry on out in two seasons. A wooden tower creaking in a 50 mph
storm can give an amateur nightmares. They are expensive to build with todays
pricing on wood.
Simple fold-over wooden towers such as a flagpole design,can be done if the
materials are availble at a resonable price.
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||||||<--- Locking pin (bolt)
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This set up can be done in a day with the right materials. The main pole can
be pulled up with a pick-up or car. A stop bar is recommended so you don't
pull the main section over with the vehicle. Place the stop bar just above
he
locking pin and bolt it into the main section but not the supports.
It also can be cranked up with a boat winch from the bottom.
-WS
--- GoldED 2.42.G1219
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* Origin: VE3SJN....Moderator....HAM_TECH (1:163/506.4)
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