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Old September 5th 06, 03:24 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 1,614
Default G5RV trimmed for voice?

Bruce Wilson wrote:
I was looking through the G5RV instructions including the original article,
and it's clear the antenna, when it is 102 feet long, is tuned for the
bottom of the bands. Anyone have any experience trimming one down to
resonate in the mid part of the voice bands?


If you will download the free demo version of EZNEC from
www.eznec.com, I will send you the .EZ model of a g5rv
and you can experiment to your heart's content.

The problem is if you shorten the series section to make
the G5RV resonant on 3.8 MHz, it will tend to resonate
on 40m at 2 x 3.8 = 7.6 MHz and on 20m at 4 x 3.8 = 15.2
MHz. You can always improve one band at the expense of
others.

You can improve 75m performance by installing a 1000 pf
silver mica cap across the twinlead at the twinlead/coax
junction but that cap needs to be removed for the other
bands. When I ran a G5RV, I used a clip on capacitor.
If you like 75m, try the cap.
--
73, Cecil http://www.w5dxp.com