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Old June 9th 10, 07:00 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 Question about "Another look at reflections" article.

On Jun 9, 8:26*am, Keith Dysart wrote:
6. Keith, using basic circuit theory, reflection coefficients and
* *analysis in the time domain, shows that Cecil's conclusions do not
* *align with expected behaviours.


I had to run an errand and, as usual, the answer popped into my head.
The problem has to do with the definition of "power". If, in a flat
system, one measures 100 watts at 100 points between the source and
the load, does that mean that there are 10,000 watts of power
available to be dissipated or radiated? Of course not! That is your
conceptual error.

Keith, your instantaneous virtual power is not *real* power until it
is dissipated (or radiated). Thus your instantaneous virtual power is
not required to obey the conservation of energy principle and all bets
are off. If your instantaneous virtual power seems to violate the laws
of physics, it is simply because you are counting it too many times or
too few times.

Instantaneous virtual power is *absolutely irrelevant* until it is
dissipated or radiated. In my resistive-source/resistive-load (no
radiation) example, nothing of value actually happens until power is
dissipated in one of the two resistors. I have accounted for all the
power being dissipated in the two resistors. Your V(t)*V(t)
instantaneous power doesn't matter unless it is being dissipated and
surprise!, it is not, i.e. your instantaneous power doesn't *count*
until it is dissipated. Please feel free to try again.
--
73, Cecil, w5dxp.com