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[AMPS] Re: swr

To: <amps@contesting.com>
Subject: [AMPS] Re: swr
From: jono@enteract.com (Jon Ogden)
Date: Sun, 3 Oct 1999 21:24:36 -0500
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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