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Old August 28th 03, 02:46 AM
Tom Bruhns
 
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"Reg Edwards" wrote in message ...
....
By the way, you've told us only half the story. What's the value of the
load impedance which maximises the reflection coefficient?


Hey, Reg, it's just a simple high-school (well, maybe first-year
college) differential calculus problem. Just let Garvin work through
it for us. Hey, good Dr., could you do that for us? Just write an
expression for |Vr/Vf| = |(Zl-Zo)/(Zl+Zo)| in terms of Rl and Xl and
find the partial derivatives with respect to those two variables, and
set both equal to zero, while letting Ro=Xo. It's mostly just a bunch
of bookkeeping. You should come up with values of Rl and Zl in terms
of Ro, and you can check to be sure that's actually a maximum and not
a minimum or saddle point. You should see a symmetry for Ro=-Xo, the
more usual limiting case.

Cheers,
Tom