Mike Monett wrote:

Yes, this is a very nice demo. Thank you for posting it.

I have a question. In demo 4, the bottom window shows the Ee field
in green, Eh in red, and ETot in black.

When the demo starts, you can only see a green and a black trace.

If you pause it just as the wave hits the end, you can now see the
red trace, Eh. (This is an actual statement and has nothing to do
with the fact I am Canadian.)

What happened to the Eh trace as the wave is initally moving to the
right? Is it overlaid by the Ee trace in green? Or is it just not
plotted?

The traces are drawn in the order Eh, Ee, and total. During the initial
forward wave, Eh and Ee are equal, so the Ee overwrites the Eh trace.

Then, when the wave hits the end and starts reflecting, the red
trace remains attached to ground, and the green trace moves up and
connects with the black trace. (Sorry for the confusing description
- you have to try it yourself to see.)

Hopefully it'll all make sense once you think about how one trace will
always win when more than one have the same value.

Now, as you single step, the green trace and the red trace appear to
be 180 degrees out of phase.

My problem here is someone wrote a web page that claims the electric
and magnetic fields are orthogonal:

http://www.play-hookey.com/optics/tr...etic_wave.html

You're making the same error that Cecil often does, confusing time phase
with directional vector orientation. The orthogonality of E and H fields
refers to the field orientations of traveling plane TEM waves in
lossless 3D space or a lossless transmission line, at the same point and
time. The E and H fields of these traveling waves are always in time
phase, not in quadrature. The graphs show the magnitudes of the waves at
various points along the line. These represent neither the time phase
nor the spatial orientation of the E and H fields.

I tried sending him an email to show if the fields were orthogonal
as he claims, it would look like a pure reactance, and no energy
would be transmitted. But he is stuck on his idea and won't budge.

Good for him -- he's absolutely correct. If the E and H fields were in
time quadrature, you'd have a power problem. But they're not. They're in
phase in any medium or transmission line having a purely real Z0 (since
Z0 is the ratio of E to H of a traveling wave in that medium). This
includes all lossless media. But they're always physically oriented at
right angles to each other -- i.e., orthogonally, according to the right
hand rule.

Now my problem is figuring out exactly what happens at the
reflection, and why the Eh field behaves the way shown in your demo.

Go for it!

Roy Lewallen, W7EL