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Old June 25th 10, 01:00 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 572
Default what happens to reflected energy ?

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