"Dick Green". wrote:>
> So, what's a fella to do? Several people flatly stated that the antenna
>will work best when operated at the resonant frequency, so I should
>retune it to resonate at 7.150 and build a matching network between the
>antenna and the 50 ohm feedline (coils, transformers, and 1/4 wave stubs
>were mentioned.)
> But I'm not so sure.
Hi Dick. I have read for years articles written by Lew McCoy W1ICP that
the antenna doesn't have to be resonant as long as it is matched to the
transmitter so you can get maximum transfer of power from the rig to the
antenna. I have used gamma matches on 40 meter verticals with very good
results. Just ground the base and tune it just like a beam. If you put
up more than one vertical, that is a very good way to make sure that the
swr is the same on all of them. I am fortunate on my 3 element array that
the swr only changes from about 1.5 to 1.8 to 1 as I switch it through
all 6 directions with out any kind of matching. When I put up the 2
element array the first time, I used gamma matching. In fact the article
I used to build the 3 element array used gamma matching. Very interesting
thread for sure!!
73 and hope you can digest all the info you are getting.
Topm W7WHY
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