On Apr 15, 8:08 pm, Cecil Moore wrote:
I will admit it when you prove that "matching the source
impedance to the line" prevents reflections from the
source. You have to run bench experiments to prove
that - no 10 cent resistor hand-waving allowed.

Ahhh. A challenge. I like it.

But first, we need to agree on an experiment that you will
find convincing. We don't want any wiggle room after the
work is done, do we?

So I propose the following:

A signal generator with 50 Ohm output impedance is connected
to the left end of a length of 50 Ohm line and another signal
generator, also with 50 Ohm output impedance is connected to
the right end of the same line.

The signal generator on the left is set to frequency Fleft
and the one on the right is set to a different frequency
Fright. The line is appreciable fraction of 1 wavelength
long at Fleft and Fright.

Step 1 - Replace the signal generator on the right with a
50 Ohm terminator
Step 2 - Observe the signal at the left and right end of
the line. The signal at the right will be a delayed
and possibly reduced copy of the one on the left.
Step 3 - Replace the signal generator on the left with a
50 Ohm terminator.
Step 4 - Observe the signal at the right and left end of
the line. The signal at the left will be a delayed
and possibly reduced copy of the one on the right.
Step 6 - With both generators operating, observe the signal
at the left and right ends of the line.

MY expected result: If no reflections are occurring then the
signal at the left will be the sum of the signals observed at
the left in Step 2 and Step 4, while the signal at the right
will be the sum of the signals observed at the right in Step 2
and Step 4.

If any reflections have occurred, the reflection will modify
the signal at the generator end (for that particular frequency)
and MY expected result will not occur.

Does this cover it?

If MY expected result occurs, you will accept that 10 cent
resistors in generators will prevent re-reflections, "realize
that you are wrong and be the first to admit it."

What say ye?

....Keith