On Fri, 15 Aug 1997 13:23:26 -0400 (EDT) CQK8DO@aol.com writes:
>In discussing the fundamental resonant frequency of an antenna
>element,
>resonance is the frequency at which there is no reactive component,
>i.e.
>J=0... It is also the frequency at which the antenna element is at the
>lowest
>impedence within that octave....
>You can verify this with any of the RF analyzers.... When i am
>installing or
>revising an antenna I simply tune my RF-1 Analyst to a frequency near
>the
>expected resonant frequency, then switch to the Z mode and rock the
>dial...
>As soon as I see which direction causes Z to decrease, I tune smoothly
>in
>that direction until Z bottoms out and begins to increase... Then I
>rock the
>dial until I have determined the minimum Z point, and that is the
>resonant
>frequency...
>
>Now, whether or not that impedence is even close to 50 ohms is another
>story
>entirely...
Only in the textbooks Denny. In the real world j0 can be, to paraphrase
Yogi Berra,
"whatever it thinks it is it is" .
Unfortunately way too many hams and others are locked into a 50 or 75 Ohm
mindset and go downhill from there.
Interested in your Autek comments, I have heard pros and cons, tell us
more please. I literally gave my MFJ "analyzer" away a few years ago;
almost unusable IMO.
73....Carl KM1H
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