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Old March 26th 04, 06:33 PM
Paul
 
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'Doc wrote in message ...
Paul,
Another suggestion, end feed a center fed dipole. That
doesn't
make much sense, but thats because I don't know how to describe
it.
In effect, run the coax ~through~ one half of the dipole to the
center where the feed point is. One way is to double the braid
back
onto it's self. The folded back braid makes up half the dipole,
the
center conductor is the 'other' half. I'm sure there are better
descriptions and pictures somewhere, I'll see if I can find one.
'Doc

Doc, I found some info on the antenna you describe. It can found at
http://www.xs4all.nl/~pa0nhc/antenne/cobra80/cobra.htm
And the weird thing is he had the exact same problem I'm having. I
think this is the solution to my problem. Thanks
Paul
KC9EYE
Hobart, IN
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Old March 26th 04, 07:00 PM
The other John Smith
 
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It is called a coaxial antenna. It is usually used in the vertically
polarized orientation, but don't let that stop you from using it in any
other orientation.



"'Doc" wrote in message ...


Paul,
Another suggestion, end feed a center fed dipole. That
doesn't
make much sense, but thats because I don't know how to describe
it.
In effect, run the coax ~through~ one half of the dipole to the
center where the feed point is. One way is to double the braid
back
onto it's self. The folded back braid makes up half the dipole,
the
center conductor is the 'other' half. I'm sure there are better
descriptions and pictures somewhere, I'll see if I can find one.
'Doc



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Old March 27th 04, 12:41 AM
Tam/WB2TT
 
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"'Doc" wrote in message ...


Paul,
Another suggestion, end feed a center fed dipole. That
doesn't
make much sense, but thats because I don't know how to describe
it.
In effect, run the coax ~through~ one half of the dipole to the
center where the feed point is. One way is to double the braid
back
onto it's self. The folded back braid makes up half the dipole,
the
center conductor is the 'other' half. I'm sure there are better
descriptions and pictures somewhere, I'll see if I can find one.
'Doc


That might be an original idea, a sleeve vertical mounted horizontally.

Tam/WB2TT


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Old March 27th 04, 01:15 AM
'Doc
 
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Paul,
I've used one of these things when portable. Worked
better than the mobile antenna, but I did use a tuner
(wasn't all that worried about losses at the time, no
harm to the tuner).
To keep the weight/cost/bulk down I used RG-58 coax (it
was going to be wound up and thrown in the trunk). If I
were going to make it a 'permanent' (no such thing!) antenna
I might use something larger, but I doubt it.
The center 'feed point' was weather proofed by sealing it
with some kind of 'goo', can't remember what it was, probably
silicon. Also found that winding a 'choke' a few feet from
the end where it came out of the folded back braid cut down
on RFI problems. Not that they were 'bad', but it didn't
hurt anything either.
I wouldn't count on it ever being a 'DX antenna' (whatever
that means), but it is an alternative...
'Doc
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