"Tarmo Tammaru" wrote in message ...
"Dr. Slick" wrote in message
om...
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 make a pont of the fact that they are *not* violating the concept of
conservation of energy


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.




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.

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.




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.

No idea. Never had to extend a Smith chart


Do some research, and you will never see an "extended Smith
Chart" for a passive network. Oh, certainly for a active device, for
stability circles and such, but passive networks can never have a rho
greater than 1.




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?




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

"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

"Tarmo Tammaru" wrote in message ...

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


But the square of the MAGNITUDE of the Voltage RC is the power
RC.

They never tell us why, and i don't think a lossy line will
increase your chances of getting rho1. In fact, i don't believe this
is possible with a passive network.





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



What is not understood is how one gets from:

Voltage R. C.= (Vr/Vi)e**(2*y*z)

where y=sqrt((R+j*omega*L)(G+j*omega*C))
and z= distance from load

To:

Voltage RC=(Z1-Z0)/(Z1+Z0) for purely real Zo
or Voltage RC=(Z1-Z0*)/(Z1+Z0)

And i have NO problems with the normalized formula,
AS LONG AS Zo IS PURELY REAL.

If Zo is complex, then Zo*/Zo is certainly NOT equal to
one!

I don't really trust this book too much, maybe that's why
it is out of print.



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



A book can always be reprinted if there is a demand.
Possibly no one bought the book because it's incorrect?


Slick