On Mon, 22 Dec 1997 08:27:39 EST CQ K8DO <CQK8DO@aol.com> writes:
>3... At frequencies away from resonance you will have reactance,
>expressed as +/- J , which affects the SWR bridge reading...
>There are combinations of J and Z which can make the SWR bridge
>look pretty good, while the antenna itself is hoplessly mistuned.
Actually, minimum swr occurs at resonance. For example, if the
antenna is 25 ohms at resonance, the swr = 2. If the frequency
is changed such that the impedance is 25+j43, the swr = 3.7, even
though the impedance is 50 ohms. You can see how it works on
a Smith Chart. (Remember those?)
Happy holidays to all.
Dave Hachadorian, K6LL
Yuma, AZ
K6LL@juno.com
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