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Old January 6th 05, 02:55 PM
Cecil Moore
 
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Gary wrote:
Thanks Cecil and to all who responded, I think I'll just put up a
center fed dipole and feed it with twinlead or ladder line and then
use the 4:1 balun in my antenna tuner.


That is a very popular configuration and works for a lot of hams. You
may need to change the length of the feedline for optimum operation.
Some ideas and information are available on my web page at
http://www.qsl.net/w5dxp/notuner.htm

One case where a 4:1 balun doesn't function well is on dipoles that are
less than 1/2WL long. For instance, the impedance looking into the
feedline for a 102 ft. dipole used on 80m may range down to 10 ohms. A
4:1 balun tries to take that 10 ohms down to 2.5 ohms. Antenna tuners
are inefficient when trying to match such low impedance values.
--
73, Cecil http://www.qsl.net/w5dxp