At 12:59 PM 3/28/2002 -0500, you wrote:
> > I believe that the logical flaw in the argument lies in discussing
> > reflected *power*. *Power* cannot reflected; only voltage and current are
> > reflected.
>
>Excellent point Kim. The term is oftentimes used as a convenience to
>represent the combined voltage and current terms. I am guilty
>of it. Taking this one step further in absolute correctness, would it be
>fair to say that neither the voltage, nor the current
>reflects? Rather, it is really the forward *wave* which is composed of
>voltage and current that reflects at the point of the
>impedance mismatch?
Thanks, Paul. Yes, I *think* that would be correct. I'm sure someone will
tell us otherwise if it isn't.
>Nevertheless, the result of the reflected wave results in *power* being
>absorbed by some resistive termination...hopefully, 100% of
>it into the antenna...other times inside the resistive portion of the
>source generator (e.g., fixed Z transmitter) as a result of
>wave reflection at the load.
>
>-Paul, W9AC
Rather than being absorbed, what if we thought of it as having never left?
While a very poor analogy, we might think of it a bit like racing the
engine in a car while the transmission is in neutral: lots of sound and
fury, but no power goes anywhere. All power is dissipated within the
engine itself. Under certain conditions, we could even destroy the engine
this way. The transmission provides the impedance match that allows for
efficient power transfer. Lots of equally poor analogies come to mind, but
this is how my pea brain thinks about this stuff, anyway.
Kim Elmore, N5OP
Kim Elmore, Ph.D.
"All of weather is divided into three parts: Yes, No, and Maybe. The
greatest of these is Maybe" The original Latin appears to be garbled.
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