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Old May 29th 05, 01:26 PM
hasan schiers
 
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Perfecto, Reg!

This is exactly what I was looking for ...but I had forgotten you had
written this little jewel.

I am a bit surprised at the small effect on losses in the number of radials
once one gets above 8 radials of 20m length.

I need to play more with wire size (confounded mm!)

Thanks again for your contribution of this program. 73

....hasan, N0AN
"Reg Edwards" wrote in message
...

For single-band operation, an autotransformer comes to mind.
Wind a coil with about 12 microhenries of inductance. Transmitter
output goes to the top of the coil. Ground goes to the bottom.
Tap down from the top on the coil for the antenna feedpoint.
The transformation ratio is roughly equal to the square of the
turns ratio.
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73, Cecil http://www.qsl.net/w5dxp

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Cec, it seldom works. You forgot to mention the most important
parameter is the input impedance to the antenna.

For an analysis of an inverted-L or vertical antenna, plus tuner L and
C component values, download in a few seconds program ENDFEED from
website below. No unzipping inconveniences. Run immediately. Easy to
use.
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Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
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