[AMPS] Hold on - SWR meter placement

[Jon Ogden]

measures wrote:

>>>€  In a slotted line, when the swr is less than perfect, the voltage on 
>>>the line varies with position.  
>>
>>What is "less than perfect" SWR, Rich?  I thought SWR was a ratio of max 
>>voltage to min voltage on the line.  What is meant by "less than perfect"?
>>
>More than 1 to 1.  

Still insisting on YOUR wives tale, Rich?  All the rest of us and all of the textbooks that talk about VSWR are wrong?

Look at it another way.  If I run 100 Watts into a transmission line that is LOSSLESS, then there is a specific voltage and a specific current on that line.

According to Ohms law and the law of conservation of energy, if the impedance of the line is constant then the voltage/current ratio MUST be constant along the line.  In other words, a voltage peak is a current null, etc.  Then it must also follow that the ratio of the peak voltage to the minimum voltage must also be constant.  VSWR is the ratio of peak to minimum voltage along the line.

Rich, what you suggest is against all the laws of physics.

If the impedance along a transmission line is constant and the line is lossless (or nearly so for the real world), the VSWR will remain constant!  PERIOD!

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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