Cecil Moore wrote:
Roger Sparks wrote:
While it is logical to add the voltages from Column B and Column C,
the two voltages are often in opposition so they are not "seen" by
Rs. As a result, we must have a reflection from Rs that I am not
taking into account.

It's not a "reflection" of a single wave, Roger, it is
a "redistribution" of energy caused by superposition
of two waves accompanied by interference. Eugene Hecht
explains it all in Chapter 9: Interference in "Optics".

For anyone who thinks he is already omniscient
about EM waves, I would highly recommend reading
Hecht's chapter on interference.

Here's an even better idea.

Dump Hecht and read about interference in Born and Wolf. Chapter VII (in
the 7th edition) is one of the main contributions. I particularly like
Section 7.6. In this section the authors derive a general set of
equations that deal with all sorts of reflection configurations. There
is no need to worry about constructive or destructive interference. The
equations smoothly transition from one to the other as appropriate. The
equations don't fall apart as the reflection goes to zero. No
"redistribution" is needed.

This is the way physics typically works; it is not necessary to separate
superposition from interference or separate constructive from
destructive. If the analysis and the equations are correct they will
work for a wide range of parameters. Equations that must be fine-tuned
for every possible change in reflection coefficient or other parameters
are very limited and most troublesome.

73,
Gene
W4SZ