On Apr 4, 9:25 pm, Cecil Moore wrote:
When it comes to a source, I seem to have been wrong
about that. A source seems to create its own physical
boundary.

Truly, you have constructed a world view that is much more
complicated than necessary.

Consider the 75 Ohm resistor at the right hand end of a 75 Ohm
transmission line. The load is matched to the line and there
is no discontinuity and (dare I say it?) no reflection.

Want a generator at that end? Put an ideal current source
in parallel with the 75 Ohm resistor. What do you have but a
generator with a 75 Ohm output impedance. And no discontinuity.

Do all the above with a 50 Ohm resistor. As a load, the 50
Ohm resistor is a discontinuity with reflections. As a
generator it has a 50 Ohm output impedance and there is a
discontinuity.

Is not the symmetry rather enticing? And simple?

And using superposition, you can analyze the incident wave
and its reflection, and along with the generated wave, sum
them to obtain the total system response.

Truly elegant. And all so simple.

....Keith