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Old July 6th 05, 11:07 PM
Owen
 
Posts: n/a
Default Calculating loss on a mismatched line


Apparently, Michaels described in "Technical Correspondence" in QST
NOV 1997 a method for calculating loss on a mismatched line.

I don't have the article, and haven't been able to find it on the net,
so I am working from references to it that I have seen, mainly in
Usenet.

Apparently, the method involves calculation of a factor (let's call it
MR) as MR=|(Zl-Zo*)/(Zl+Zo)|, and the line loss between two points is
given by 10*log((1-MR1**2)/(1-MR2**2)) where MR1 and MR2 are the
values for MR at points 1 and 2.

I have compared the results of this on lines with Xo0 and high VSWR,
and the results are identical to calcuating the loss by subtraction of
Real(VI*) at point 1 from Real(VI*) at point 2.

Has anyone a link to, or a reference to the derivation of the formula?

Owen
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