[AMPS] SWR and line length, etc.

[Jon Ogden]

Roger D. Johnson wrote:

>After playing with my electronic Smith chart program, the answer is
>obvious. The impedance plot of an antenna can appear anywhere on
>the chart. The point nearest the chart center will be the point of
>lowest
>SWR and can be quite reactive.

That's correct.  An antenna's S11 plot can vary all over the place.  And 
yes, the lowest SWR will be at the point of least reactance, but not 
necessarily zero reactance.  As a matter of fact, a point with some value 
of reactance could end up having less SWR than a point with zero 
reactance.  If an antenna is 100+j0 Ohms at one frequency and 50+j10 Ohms 
at another frequency, the 50+j10 Ohm point has more reactance for sure, 
but less SWR.  Gotta look at those SWR circles!

73,

Jon
KE9NA




--------------------------------------------------------------------------
The Second Amendment is NOT about duck hunting!


Jon Ogden

jono@enteract.com
www.qsl.net/ke9na

"A life lived in fear is a life half lived."


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