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Old May 22nd 08, 07:52 PM posted to rec.radio.amateur.antenna
Tam Tam is offline
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First recorded activity by RadioBanter: Jan 2008
Posts: 42
Default 75m/30m, 40m/17m Dual Banders


"Cecil Moore" wrote in message
news
There was a discussion the other day about stub loaded
dipoles. A 30m dipole loaded at each end with a 30m/4
shorted stub is resonant on both 30m and 75m. A 17m
dipole loaded at each end with a 17m/4 shorted stub
is resonant on both 17m and 40m. The stubs provide
inductive loading on the lower bands resulting in
"shorty" dipoles, shrunk by about 20%.

I've summarized two such antennas on my web site at:

http://www.w5dxp.com/dualband.gif
--
73, Cecil http://www.w5dxp.com

It might be easier to do what I did. I have 17 and 40 meter dipoles
connected to a common feedpoint. The 17 m dipole is the supporting element,
hung between two trees at about 50 feet. The 40 m dipole is arranged as an
inverted V. The trees are not far enough apart to have the 40 m dipole on
top. Either way, the 40 m has to be resonated first.

Tam/WB2TT