On Apr 10, 9:01*am, Cecil Moore wrote:
Keith Dysart wrote:
As I expected, you claim that the situations are
*completely* different. And yet the voltage, current
and energy distributions are identical. There are
no observable differences. And yet you claim they
are *completely* different. And yet there are no
observable differences. And yet....

I did NOT claim that the situations are *completely*
different. I said that some conditions are different
and some conditions are the same. Voltages and currents
are the same yet there is certainly a difference between
an open circuit and a short circuit. Besides, in the
real world, cutting the line would certainly cause
observable differences.

Tis a puzzle, isn't it.

Nope, if you were born without your five senses,
you would feel that way about everything in existence.
Why do you deliberately choose to remain handicapped
by ignorance?

A bit of modulation would cure up the mystery for
you. If any modulation crosses the node, it is a
good bet that wave energy is carrying the
modulation.

When you modulate the carrier, the resulting signal
has many frequencies. Unless great care is taken
with the choice of modulation frequencies and
carrier frequencies, they will each have nodes
at different places on the transmission line. Without
a common node, there is no place that energy
does not cross, hence modulation makes the
question moot. In effect, the standing waves
of the various frequency components do not line
up. (Remember superposition works, for voltages).

If care is taken with the selection of modulation
frequencies with regards to the carrier, then nodes
can be created on the transmission line and neither
the carrier nor the modulation will cross such a
node.

If phase locked TV signal generators
equipped with circulator load resistors are
installed at each end of a transmission line,
the TV signals can be observed on normal TV
sets crossing the standing wave nodes as if
they didn't exist.

Which they don't, as explained above.

Removing the modulation
is unlikely to reverse the laws of physics.

True, but it can change whether there are nodes.

And we know from circuit theory that we can cut
a conductor carrying no current without affecting
the circuit. Why should it be different here?

Please prove that a short circuit and an open circuit
are identical.

An open circuit is just as useful as a short circuit
when no current is flowing.

Please present your new laws of physics that allow
EM waves to reflect off of EM waves in the complete
absence of a physical discontinuity.

Again, not my claim.

Seems your theory requires such. Please explain how
reflections can occur at a passive standing wave node
without EM waves bouncing off of each other.

Energy and momentum both must be conserved. A causeless
reversal of energy and momentum is impossible whether
it is a bullet or an EM wave.

What causes energy to flow into and then out of a capacitor?
Look for your answer there.

But using your previous approach
for analysis, perhaps we should insert a zero length
line of the appropriate impedance to provide the cause
for the reflection, if you insist on a reflection.

Please produce an example of
a real world transmission line that would support your
100% reflection. Hint: what would be the Z02
characteristic impedance in the reflection
coefficient equation, (50-Z02)/(50+Z02) = 1.0 ???

That is just too easy...
(50-Z02)/(50+Z02) = 1.0
50 - Z02 = 50 + Z02
-2 * Z02 = 0
Z02 = 0
That wasn't so hard, was it?

...Keith

Keith Dysart wrote:
If care is taken with the selection of modulation
frequencies with regards to the carrier, then nodes
can be created on the transmission line and neither
the carrier nor the modulation will cross such a
node.

Please prove your assertion on the bench. Until you
do, there is little left to discuss.

Please produce an example of
a real world transmission line that would support your
100% reflection. Hint: what would be the Z02
characteristic impedance in the reflection
coefficient equation, (50-Z02)/(50+Z02) = 1.0 ???

That is just too easy...
(50-Z02)/(50+Z02) = 1.0
50 - Z02 = 50 + Z02
-2 * Z02 = 0
Z02 = 0
That wasn't so hard, was it?

Now build one. Be sure to verify that you can transfer
energy from end to end. Until you do, there is little
left to discuss.
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:
Keith Dysart wrote:
If care is taken with the selection of modulation
frequencies with regards to the carrier, then nodes
can be created on the transmission line and neither
the carrier nor the modulation will cross such a
node.

Please prove your assertion on the bench. Until you
do, there is little left to discuss.

And if you do, the distributed network model will
have to be overhauled.
--
73, Cecil http://www.w5dxp.com

On Apr 11, 9:32*am, Cecil Moore wrote:
Keith Dysart wrote:
If care is taken with the selection of modulation
frequencies with regards to the carrier, then nodes
can be created on the transmission line and neither
the carrier nor the modulation will cross such a
node.

Please prove your assertion on the bench. Until you
do, there is little left to discuss.

Speculating that this is your way of asking for an
explantion...
With a shorted line, nodes occur every 90 degrees. These
90 degree nodal points are at different places on
the line for different frequencies because the
wavelengths are different. With the nodes at
different physical locations for the different
frequencies, when you sum the responses for all of
the frequencies there are no longer well defined
nodes.

If the frequencies are rational numbers, then
nodes for the total response will exist at the lowest
common multiples of the wavelengths, but it will
typically take a very long line to find one.

...Keith