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- Created: 07 March 2014
- Last Updated: 07 March 2014
[ This was written in April of 2007, and appeared in "The Repeater", our local repeater club newsletter. ]
After a lot of vacillation, I finally decided what antenna to put up.
After I started to realize that the "windom" antennas that are advertised and sold are not really windoms, I decided to put up an off center fed dipole.
The popular "windoms" that are out there all have about 1/3-2/3 ratio off center feeds, and radiating vertical sections (a-la g5rv). Some radiating sections are open wire and some are even coax. Then on top of that they call out specific lengths of coax to the shack.
Then I finally started getting some real information. An off center fed (OCF) dipole fed at the 1/3-2/3 point is resonant based on total length, and instead of a 75 ohm feed point they have anywhere from 200 to 600 ohms. The interesting thing is that it is multi banded with no traps. An 80m length of wire will do 80, 40, 20, and 10 (not 15) (and 6 too), all with nearly the same feedpoint impedance.