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Old January 23rd 06, 03:44 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Help with J antenna design

JIMMIE wrote:
Thanks Cecil, I was concerned about spacing of the stub more than
anything else. I guesstimated this should be about a foot.


The bottom 1/4WL is a quarter-wave matching stub, either open
or shorted. If it is open, you have a Zepp antenna, and they
used to use open-wire transmission line for that. One foot
spacing may be a little much. Rule of thumb - 1% of a wavelength
would be about eight inches on 20m.
--
73, Cecil http://www.qsl.net/w5dxp