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Old April 20th 07, 10:53 PM posted to rec.radio.amateur.antenna
JIMMIE JIMMIE is offline
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First recorded activity by RadioBanter: Jul 2006
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On Apr 19, 12:40 pm, Cecil Moore wrote:
Jimmie D wrote:
Cecil, I was thinking of trying your no= tune antenna and the 16 ft piece
may not be doable at my QTH, I have to keep it all hidden behind the bushes.
Could this piece be replaced with a circuit using lumped LC values.


That would work at one frequency but not others. What I do with
the 16 foot length is coil it into a spiral of 4 turns. The
diameter of the spiral is about 16 inches and the overall
length of the spiral is about 24 inches. That should fit
"behind the bushes". I use a piece of fiberglass rod to
which to tiewrap the coils.

There's nothing magic about the 16 foot length. It is only
necessary if you need to vary your length from 0 to 31 feet.
In actual practice with my 130 foot dipole, I only needed
to vary the length from 0 to 23 feet so I made the "16 ft"
section just another 8 foot section. The 16 foot section
was required from 3.5-3.6 MHz and I never use those frequencies.
That's why I could get away with replacing the 16 ft section
with another 8 ft section.
--
73, Cecil, w5dxp.com


Thanks Cecil, I have been wanting to put up an antenna like yours for
quite a while now. Today I was doing a liittle clean up in the attic
and found a box of DPDT open frame relays that should work well for
remote switches. I should be able to run coax out to my garden shed
and and ladder line from there to the antenna locating the switches at
the shed. I can hang the dipole at about 40ft and was wondering what
the pattern would be. I was thinking this low to the ground it would
be almost an omni- directional antenna. If I could ever get all my
crap organized I could probably put together one hell of a station.

Jimmie