[AMPS] Re: The Worldwide, No Holds Barred, SWR Quiz.

[Jon Ogden]

measures wrote:

>>Jon, if you were right, SWR meters would be useless, since readings would 
>>change as cable lengths changed!  
>
>€  they do.

No, RIch, they don't if your coax and your exciter are of the same characteristic impedance.  The impedance of the load will appear to vary as you move down the line (if it is different than the characteristic impedance), but the SWR won't.

The only time the SWR will change as you change the length of the transmission line is if that transmission line is of some impedance that is different than the characteristic impedance of the source and the load.  If the transmission line is the same as the source, the impedance will vary with length but the VSWR won't.  If the transmission line is the same impedance as the load, neither the VSWR or the impedance will change with line length.

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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