Larry Molitor wrote:
>>? To find out if this is really true, why not try it? All that's needed
>>is a 50 +/- j0 ohm termination and a halfwave of 75 ohm coax (c.10.5 '
>>for 10m). Measure the SWR at the half-wave and the quarter-wave points.
>
>Rich, glad you said it so I didn't have to.
This is correct. Once you change the characteristic impedance of the
transmission line, you are no longer operating in a 50 Ohm system.
See the problem here is that you have this set up:
A 50 Ohm load, a 75 Ohm transmission line of a half wavelength, and an
SWR meter based on a 50 Ohm system.
The 75 Ohm line now acts as an impedance transformer.
The cases I SPECIFICALLY was talking about was one where the LINE
IMPEDANCE IS 50 OHMS! I HAVE ALWAYS STATED THAT VERY SPECIFICALLY!
Yes, the Smitch Chart is NORMALIZED to whatever impedance you so choose.
If you choose 50 Ohms as your normalized impedance, then what I have said
is correct.
I wish Mr. Measures would stop thinking he is smarter than all of
academia.
73,
Jon
KE9NA
-------------------------------------
Jon Ogden
KE9NA
http://www.qsl.net/ke9na <--- CHECK IT OUT! It's been updated!!!!!
"A life lived in fear is a life half lived."
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