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Author Topic: Trees are too close for the wire antenna  (Read 3764 times)
WA3SKN
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Posts: 5458




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« Reply #15 on: September 27, 2011, 11:02:40 AM »

You have a bad connection!
Connect a known, good, dummy load to your rig and check the SWR.  Then move it to the other end of your feed line and check the SWR.  This verifies the rig and coax.  Then you can take down the antenna and look for loose and poor connectors, solder connections, etc.  Trees make little difference at HF unless weather gets into things.
The nice part is you can use a simple VOM to check this... no need for an expensive antenna analyzer or the like.
73s.

-Mike.
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KG6MZS
Member

Posts: 476




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« Reply #16 on: September 27, 2011, 11:23:26 AM »

You have a bad connection!


As one who had the same symptoms and blamed the trees, that's what I would put my money on.

Of course I could never get my balanced-line antennas to work for years until someone pointed out I needed to put a jumper on the tuner.   I might not be the best source of advice  Embarrassed
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WB6BYU
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Posts: 13176




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« Reply #17 on: September 27, 2011, 11:30:56 AM »

I've often run antennas through trees, usually for portable setups.  There may be a little change,
but not as much as I get from one installation to the next due to the antenna height, relative
positions of the wires, etc.  It has never been so bad that I couldn't operate.

The one time I saw that much variation due to a tree branch was with a 80m "Hamstick Dipole".
There was a branch about 5 feet away from one end, and the SWR shifted significantly as it
blew around in the wind.  But that is a VERY narrow-band antenna, and such behavior is
to be expected.

I agree with the others - if the SWR changes enough that you can't operate, something else is
wrong with the antenna.  It might be an intermittent coax connection, or you may be pulling
up too much tension on the antenna and have a break at the center insulator and/or inside
the wire insulation.  If you had the same problem with two different antennas, focus on those
cables / connectors / etc. that are common between the two installations.


(I'm presuming that you are using a tuner with the antenna already, and that it is properly
adjusted to match the antenna in some conditions, but that the SWR shifts to where the
SWR is too high - probably over 2 : 1.  If this doesn't describe your situation, please be
more explicit exactly how you are matching the antenna, what bands this happens on, the
range of SWRs you are seeing, etc.  That will help us to diagnose the problem.  Simply
having high SWR on an OCFD - or a true "Windom", or even a G5RV - without a tuner is not
at all unexpected, and isn't a sign that anything is wrong.)
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N4MJG
Member

Posts: 504


WWW

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« Reply #18 on: October 07, 2011, 12:29:33 PM »

Guys,

The swr is fine when i checked on it tune fine and i found out about the trees  between those 2 trees from front and back they are about 94 ft beween those 2 trees and the tree in back is trimed ! they still have to come back finish the job and put wire back up ! as i saying i was using SWR ANALYZER showing 1.1 each band some are up little but not much i check all the connection all good !

And.......i checked the line make sure they are not broken or any thing ! ,but i did find some info. other atenna as well !! i guess need to learn more on these things .i may not be smart but thats the fun thing to learn !! Grin

You guys are so cool to help out other, i think you all for helping !!!!!!!!
I will try other to see what works or not working may have study on those wire antenna more. Wink

73
Jackie
N4MJG
General lic. since 2007
Been Hamming 10 years !
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