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Old August 31st 03, 03:35 PM
Tarmo Tammaru
 
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"Dr. Slick" wrote in message
om...
"Tarmo Tammaru" wrote in message

...
"Dr. Slick" wrote in message
om...


But they never explain WHY a lossy line can INCREASE the
reflected power! The lossless line would not attenuate the reflected
wave at all!

I don't trust their claims on this.

If you get more power reflected than you send into a passive
network, you are getting energy from nowhere, and are thus violating
conservation of energy.


But the reflection coefficient is for Voltage. I think the clew lies in "The
main point of interest lies in the fact that we cannot, in general,
superpose the average powers carried by incident and reflected waves on a
dissipative line, although we could do so on a lossless line" A/C/F
.

I don't see the problem. 100 /_30 degrees divided by 2/_5 degrees is

50/_15
degrees. Different phase angle. By general case they mean not the

lossless
case.



I believe you mean 50 @ 25 degrees.


Yeah, I started typing this line before I had decided what numbers to use.



Also, they go from equation 5.12 to 5.13 without showing us how
they got there.


They use the identity e**jx = cos x + jsin x



Yes? And? How did they get the Zo=(Zn-1)/(Zn+1) from this?


I think the math is the same as for a lossless line

As I said out front. The book is copyrighted 1960. There is a certain

life
to these things.

Tam



But it seems to be out of print, perhaps with good reason...


Slick

The "print file" for a book used to be stored on hundreds of tin or lead
plates. Two N pages per plate. After printing some number of books, these
plates would have been recycled. I don't know that there was not a newer
edition.

Tam/WB2TT