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Old May 14th 04, 05:45 PM
Mark Keith
 
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Cecil Moore wrote in message ...
Larry D wrote:
Can anyone tell me the impedance I can expect to see,
also any tips on matching it? Thanks!


The VERT1 vertical that comes with EZNEC is 1/4WL on 40m.
It will be 5/8WL on 17m. (7.2 * 2.5 = 18) EZNEC sez the
feedpoint impedance on 17m will be about 100-j470 ohms.


This is what I ran when I had my 40m GP up. It worked both 17m and
40m.
My old elnec model of that antenna showed appx 48.4-j213 ohms on 17m.
But I had sloping radials. Maybe that made a difference. I used an
ungrounded series coil to tune for 17m, and the SWR was very low. I
had a 24v DPDT relay that I used to bypass the coil for 40m use.
Otherwise, it would be resonant about 6.9 mhz. I had the transformer
here in the shack, and when I changed bands, I would just plug, or
unplug the transformer from my power strip. MK