Standing-Wave Current vs Traveling-Wave Current
 

Roger wrote:
Maybe we should be considering a perfect POWER source, which could only
emit power, never absorb it. The power out would be defined by load
impedance, just as it is for the perfect voltage source.

I have been using such a source as an example for years.
I call it the SGCL, signal generator equipped with a
circulator and load resistor. Here's the diagram.


100wSG---1---2----
\ /
3
|
R

No reflections incident upon the source because they
are all dissipated in the resistor R. It's a great
way to simplify examples.
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

Keith Dysart wrote:
Similar to the reflected voltage for the perfect
voltage source, the reflected current cancels leaving
just the current from the perfect current source.

Zero power dissipation in a Thevenin equivalent
source equates to maximum power dissipation in
a Norton equivalent source. That sure shoots
down any argument about dissipation in the source.
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

Keith Dysart wrote:
And a Thevenin source can be transformed into an
equivalent Norton source. Example...

A 100 V ideal voltage source in series with 50 ohms
has exactly the same output characteristics as a
2 amp ideal current source in parallel with a 50 ohm
resistor. Test using any load impedance: open, short,
any resistance value.

Indeed, take a look at the internal power dissipation
for an open and short and tell us again why those
sources are identical.
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

Keith Dysart wrote:
Cecil Moore wrote:
Your model doesn't even require the
EM waves to obey the laws of physics. It's a lot
like my mother's model which requires only God.

Are you saying that charge can not be used to
understand circuit behaviour? Are all the books
wrong? Please expand.

Your EM waves reflect when there is no reflective media.
That is a violation of the laws of physics. Please
demonstrate two light waves reflecting off of each other
in free space.
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

Roy Lewallen wrote:
So far I've seen a number of comments that claim my analysis is wrong
for one reason or the other, in spite of the fact that it correctly
predicts the line behavior as verified by SPICE.

Roy, you wrote down the equation for V(x,t) for a
standing wave voltage. Now write down the equation
for I(x,t) for a standing wave current and tell us
again how to use that standing wave current with
its constant phase at different points up and down
the line, to measure the delay through the line.

Since Roy has ploinked me, he will ignore this posting.
Would some kind soul please reply to this posting so
Roy will see it? Thanks.
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

Roy Lewallen wrote:
So far I've seen a number of comments that claim my analysis is wrong
for one reason or the other, ...

Would you mind sharing those reasons with us?
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

Roger wrote:
I won't repeat that posting here, but please comment.

Will this source satisfy your needs? It is linear
and it prohibits reflected energy from reaching
the source making tracking energy rather simple.
I usually define it as a 50 ohm device but other
impedances could be chosen.

100w--1---2--
\ /
3
|
R
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

Roy Lewallen wrote:
I'd been considering
making up an analytical and quantitative analysis of where the energy
goes in a transmission line.

It would certainly be informative to see how you get
those reflected voltages and reflected currents to
exist without energy.
--
73, Cecil http://www.w5dxp.com

Standing-Wave Current vs Traveling-Wave Current
 

On Dec 31, 12:43*am, Cecil Moore wrote:
Keith Dysart wrote:
A voltage source has two sides? Explain!

All of my references illustrate that voltage source
with two leads. Please pass a TV signal through it
to prove it is a zero impedance.

Oh that is what you meant. So an amplifier has 4 sides?

Anyway, examples of what you are looking for exist
in most amplifiers. They are often called blocking
capacitors. They charge to the DC voltage but pass
the signal. They are not particularly good voltage
sources, but that is their role in the circuit, and
they do it admirably well.

...Keith

Standing-Wave Current vs Traveling-Wave Current
 

On Dec 31, 1:32*am, Cecil Moore wrote:
Keith Dysart wrote:
Cecil Moore wrote:
Your model doesn't even require the
EM waves to obey the laws of physics. It's a lot
like my mother's model which requires only God.

Are you saying that charge can not be used to
understand circuit behaviour? Are all the books
wrong? Please expand.

Your EM waves reflect when there is no reflective media.
That is a violation of the laws of physics. Please
demonstrate two light waves reflecting off of each other
in free space.

Do you ever answer a direct question?