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Old April 16th 04, 02:15 AM
Cecil Moore
 
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King Zulu wrote:
The impedance will still be 50-to-70 ohms if you add the extra
half-wavelength to just one end of the antenna.


Actually, it may be closer to 100 ohms. It's an OCF somewhat like
a "Windom" fed with two-conductor transmission line. The "Windom"
is supposed to have a feedpoint around 300 ohms.

i.e. The wire on one side of the antenna feed point (coax connection) is
still 32.5 feet, and the wire on the other side would be 65' + 32.5' plus
another 3.3', since there is no end-effect on the extra half-wavelength of
wire you are adding.


It's an interesting OCF antenna but probably subject to common
mode currents unless an excellent choke is used at the feedpoint.

You should get almost 2 db of gain in four directions (a
"cloverleaf") by doing that.


Since it's a one-wavelength antenna, it won't quite achieve a
cloverleaf pattern. It's about the same gain as a 1/2WL dipole
(6 dBi) but with a much wider horizontal beamwidth. For a 130
ft. long antenna, the cloverleaf pattern develops around 10 MHz.
--
73, Cecil, W5DXP



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