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Old April 19th 07, 05:40 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
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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