Here are the answers I've received concerning vertical antennas in trees.
I'll try to build something like that this winter...
Thanks to all who answered my question.
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Hi, I wonder if it would be ok to put a vertical at the top of a tree
in order to extend the overall length of the antenna.
I think to put up a 10m fiber-glass mast and use a tree to extend the
overall length to abt. 25m.
73, Cedric HB9HFN
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It works just fine. I have a 13 meter high pinetree with a 10M fiberrod
in the top to make a vertical for 80M. Works very fine with 20 radials.
Gives me 59++ in VK and 59+ in Japan, wrked many W stns - all with an
old FT901DM and L4B from Drake. Last week it survived a storm with
30m/sek wind. With a saw I cut all the branches over me, climed up, cut
again and so on, until I reached near the top. Now I have a very fine
tree for climbing!
For whats worth
73 de OZ2Q Frits in Copenhagen
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Cederic, I am using trees for my 2 inverted L verticals. The wires run next
to the trees and they are fastened at the bottom of the trees with large
wire staples. With these wires I have worked 149 countries so far. YES! Do
it. Be sure the mast is secure in the tree so it does not fall down.
73,
Sid. K3SME
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Yes, this will work just fine.
Suggest you make an inverted L of overall length about 50 meters and match
at the base with a series capacitor of about 500 pf. Install elevated
quarter wave radials, and feed thru a current balun.
Hope to work you on 160m for a new country Cedric. Email me for a sked in
December at your sunrise.
73, Walt
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I have a wire strung OVER a tree and it works fine, with 8 elevated
radials
of different lenghts.
73 Rag OZ8RO
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i used a vertical in 1972 that was in a 70' tall tree.
Worked very well.
Also a good lightning rod, although I never got struck.
VAL
N4RJ
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The only problem is mechanical.
You should not put straps around the tree. They may stop the sap from
flowing and the branch will die.
Don't forget the tree grows out of the top (grows up parallel to the mast)
and also grows thicker (surrounds the mast).
I put a pulley at 33m on a tree and stupidly expected it to grow higher each
year. But of course the tree grew beyond the pulley and I had to climb up
each year to put it higher.
So I think you have to mount the mast on long lag screws, with the mast a
few centimetres out from the tree. Then be prepared to trim the top once a
year.
I wonder why you say "vertical". If it is to suspend a vertical wire, would
it not be better to have the mast slanting out from the tree?
I use trees all the time, and find I must keep the wire away from the tree
as far as possible.
73
Bob Eldridge VE7BS
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73, Cedric HB9HFN
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