On Jun 24, 9:42*am, Cecil Moore wrote:
On Jun 24, 5:17*am, Keith Dysart wrote:

I assume you will claim that there is now “constructive
interference” rather than the previous “destructive interference”,
but the line conditions are the same. How does the “reflected
power” know if it should construct or destroy? The phase is the
same.

That's easy to answer. The Norton equivalent is a current source so
currents should be used in the calculations. The phase angles between
the two current components are 180 degrees different from the phase
angles between the two voltage components. If the interference between
voltages is constructive, the interference between currents will be
destructive. Hint: the reflected current phasor is 180 degrees out of
phase with the reflected voltage phasor because of the direction of
travel of the reflected wave. As a result of directional convention,
the power in the reflected wave is negative.

So destructive interference for forward/reverse voltages is
constructive interference for forward/reverse currents and vice versa.
An SWR voltage maximum (constructive voltage interference) is an SWR
current minimum (destructive current interference) and an SWR voltage
minimum (destructive current interference) is an SWR current maximum
(constructive voltage interference).

Very inventive. And the wave just knows the difference between the
50ohm
generator that is constructed in the Thevenin style and the 50ohm
generator constructed in the Norton style. Amazing waves.

And now the explanation for the mixed constant power mixed Thevenin/
Norton
generator is ...?

....Keith

On Jun 24, 8:39*pm, Keith Dysart wrote:
Very inventive. And the wave just knows the difference between the
50ohm
generator that is constructed in the Thevenin style and the 50ohm
generator constructed in the Norton style. Amazing waves.

Repeating myself - it is not necessary for you to imagine magical
smart waves. Ignorant people invent magic and metaphysics to explain
away their ignorance. All you need to do is to alleviate your
ignorance concerning the laws of physics which those ordinary EM waves
are obeying. *Externally*, it doesn't matter whether you use voltage
superposition, current superposition, or EM field superposition - the
results are identical. Every EE professor I ever had warned me about
trying to look inside a Thevenin or Norton source at the power
dissipation in the source resistor. For instance, their internal
dissipations are exactly opposite for shorts and opens so exactly why
should you expect the internal interference levels to be the same?
When the Thevenin source is dissipating all the power inside the
source from being connected to a *short-circuit*, it is experiencing
total constructive interference. When the Norton source is dissipating
all the power inside the source from being connected to an *open-
circuit*, it is experiencing total constructive interference -
opposite external conditions causing exactly the same phenomenon
inside the two source boxes.

And now the explanation for the mixed constant power mixed Thevenin/
Norton generator is ...?

Neither the Thevenin equivalent source nor the Notron equivalent
source is "constant power". The Thevenin equivalent source is a
constant voltage source with a series source resistor and the Norton
equivalent source is a constant current source with a shunt source
resistor. A constant power source is conceivable but it would either
need a circulator plus load, have a pretty sophisticated feedback
system, or be driving an ideal instantaneous antenna tuner.
--
73, Cecil, w5dxp.com