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Old August 31st 07, 09:08 PM posted to rec.radio.amateur.antenna
Neno Neno is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 4
Default Vertical antenna problem


"Cecil Moore" wrote in message
. ..
neno wrote:
What do You suggest?
To cut only radials to 3.25m or vertical and radials to 4.7m?
What is better?


Or (3) you could leave the radials as they are
and shorten the vertical wire.

The physical environment will shift the
resonant frequency away from that predicted
by EZNEC as modeling is not an exact science.

Any of the three choices will work and none of
them will result in the exact resonant frequency
you desire. In the end, to get the frequency
exact, you will be required to "cut and try" in
an iterative process that often forces you to
add back one inch of the two inches you just
removed. :-)
--
73, Cecil http://www.w5dxp.com


I decided to cut radials because it was the easiest job considering that
vertical is elevated 9m up the ground.
I cut radials to 3.25m and now the SWR is 1.3:1 on 14.020 .
I left the vertical to 5.1m .
I will test the antenna this days.
Thanks for help.
Eznec was very helpful also.
73 9A4MN Neno