At 09:02 AM 11/12/96 -0500, you wrote:
> This is primarily for Fred, K1VR, but all are welcome.
>
> The original shunt feed article by John True, W4OQ and later N4BA,
> from Ham Radio, May 1975, is still very up to date. The omega match
> will work fine, sometimes in reverse direction. Original shows a
> series capacitor and a shunt capacitor across the coax feed.
> Sometimes the shunt capacitor needs to be a smaller value on the other
> side of the series cap. That is between the bottom of the gamma rod
> and ground.
>
> Gary Breed, K9AY, wrote an update on using two wires in parallel to
> broaden the match bandwidth in an issue of the Low Band Monitor by
> Lance Johnson Digital Graphics, K0CS is the editor.
>
The True article in HR is a classic. I recommend all looking to build a
shunt feed
antenna read it several times.
>From Oct 75 QST, W1FB and W5RTQ have artilces on building shunt fed
antennas. Both are quite helpful. Dec 77 CQ, W5JJ on verticals. And, from
ARRL Ant Comp Vol #2, page 36, K5YNR on unipole antennas.
I feed the grounded antenna at the top in a uni-pole configuration, with a
large driven element (same size as the 25.) I use a step-up L network
(series L, parallel C) and get good performance.
GL and cu on 160!
Craig
Craig Clark
soon to be ex-NX1G
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