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Old August 31st 03, 04:05 AM
Dr. Slick
 
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"Tarmo Tammaru" wrote in message ...

I can't scan the whole chapter, and part of the next. You should be able to
get your library to borrow the book for you. Or, look at some other college
textbook under lossy lines. 5.2B is straightforward enough:

Zo=(1/Yo)=SQRT[(R+jwL)/(G+jwC)]=Ro+jXo

Tam/WB2TT



I've looked at the 9 pages you sent me, and I'm not certain what to
tell you.

They say, "the fact that the rho may exceed unity on a dissipative
line does not violate a condition of power conservation (as it would
on a lossless structure)."

On the one hand, I give them creedence for addressing the
concept...it's what i've been saying all along.
However, they don't explain why a lossy line can INCREASE the
reflected power! The lossless line would not attenuate the reflected
wave at all!

They also mention that the normalized load impedance Zn=Zr/Zo does
NOT have the same angle as Zr because Zo is complex in the general
case. This may or may not make their example moot.

And i don't trust their Smith Chart extended out to 1+sqrt(2) for
a dissipative line. Maybe for an active network, but not a passive
one.

Also, they go from equation 5.12 to 5.13 without showing us how
they got there. Perhaps they just copied it out of another book and
used the formula incorrectly.

Certainly text books can disagree, just as the "experts" often do.

Maybe this book is hard to find because it's out of print because
nobody trusted it.


Slick