Roy Lewallen wrote:
Roger wrote:

I agree that we would have the same problem with a perfect current
source which had an infinite impedance.

How about using a perfect POWER source, that could not absorb power.
Output power would be limited by the external impedance.
Mathematically, the perfect POWER source would be described by

Ps = (Vp^2)/Zvp = Zip * Ip^2 where Ps = maximum power output, Vp =
voltage from perfect voltage source, Zvp = 0, Zip = infinity, and Ip =
current from a perfect current source.

The power output could be infinite, but power could never be absorbed
by the source.

Just as for both perfect voltage and perfect current sources, the
actual power output would be limited by external loads.

The impedance of the perfect POWER source would be Vp/Ip, both
controlled by external loads. To me that means that the output power
from the perfect POWER source would follow the impedance presented by
the load, but power going into the source would be defined as being zero.

Would the "perfect power source" be acceptable to you?

No. As I mentioned on another thread, this is a nonlinear device, which
would not permit using the linear circuit analysis I used. It would
require reverting to fundamental differential equations, which I'm not
willing to do. I'll be willing to use absolutely any linear source
(which doesn't change during the analysis period) you can devise. Any
linear source can be reduced to a Thevenin or Norton equivalent to
produce identical results.

Can't your concept of transmission lines deal with linear sources? If
not, why not?

Roy Lewallen, W7EL

No, my concept of transmission lines deals fine with linear sources, it
is the non-linear constant voltage source and constant current source
that can not handle a second source of power arriving at a time later
than the original pulse.

Thank you for much thoughtful discussion. I have learned a lot, and
sharpened my skills. I won't drop the topic, because it can bear great
fruit, but let's you and I drop it for a while.

You may be right about differential equations needed for an perfect
POWER source, but so far, I don't think so. I am being honest that I
think your analysis applies up to the point of using the -1 reflection
factor at the source. In fact, I will probably use it in the future,
with an attribute to you.

Following Keith's post discussing zero voltage as a current source, I
can see why you might insist on using the -1 reflection factor. As time
passes, I will try to improve the concept of the perfect POWER source to
see if that can bridge the conceptual differences, but retain the
relative simplicity of sine waves adding.

73, Roger, W7WKB