Phil T. (VA3UX) wrote:
>Jon has said that SWR is constant regardless of line length or position of
>the SWR meter (witness the Smith Chart - it says so ). Absolutely right.
Thank you.
>
>Rich says but...the SWR reading DOES change if I move the meter ahead or
>back in the line, in the real world. Also absolutely right. The SMith
>Chart says this shouldn't happen, but it does anyway.
In the real world, perhaps not. But everything specified has been ideal.
In the real world, we have things such as imperfections in our cables
causing impedance discontinuities, we have PL-259 connectors which aren't
really "50 Ohm" connectors, every connector-cable interface has a slight
discontinuity, etc. We also have the thing known as loss. All these
contribute to a different experience than what is the theoretical ideal.
Perhaps Mr. Maxwell has yet another explanation. I am interested in
that. But when speaking in terms of theory and the reasons behind it,
you always start with the ideal case which can easily be proven
mathematically and then make exceptions for real world behaviours.
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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