Walter Maxwell wrote:
Well Owen, then how do you explain re-reflection at the souce in the absence of z virtual sc or oc?

I'm not Owen but in S-Parameter terms it is explained by:

b1 = (s11)(a1) + (s12)(a2) = 0

When (s11)(a1) equals -(s12)(a2), there is total destructive
interference in the direction of b1 toward the source. That's
the wave cancellation that is associated with your sc and oc.
As the Florida State web page says:

http://micro.magnet.fsu.edu/primer/j...ons/index.html

"... when two waves of equal amplitude and wavelength that are
180-degrees ... out of phase with each other meet, they are not
actually annihilated, ... All of the photon energy present in
these waves must somehow be recovered or redistributed in a
new direction, according to the law of energy conservation ...
Instead, upon meeting, the photons are redistributed to regions
that permit constructive interference, so the effect should be
considered as a redistribution of light waves and photon energy
rather than the spontaneous construction or destruction of light."

In a transmission line with only two directions, a "redistribution"
certainly implies a reversal in direction of the wave energy
involved in the wave cancellation, i.e. a re-reflection.

On the above Florida State web page, one can set the two waves
to the same frequency, same magnitude, and opposite phase and
observe the wave cancellation. Question is: What happens to
the energy in the canceled waves in a transmission line?
Answer: re-reflection in the opposite direction.
--
73, Cecil, w5dxp.com