Sal M. Onella wrote:

What did I say wrong?


As always, Ian has done a much better job than I could have, so there's
not much point in trying to repeat what he said.

But I did write up a lengthy essay several years ago, in response to the
same insistent rantings about reflecting waves of average power that's
still going on in this newsgroup, and it has some numerical examples
with a very simple circuit which illustrate the problems with what you
said. You can get it at http://eznec.com/misc/Food_for_thought.pdf. A
little past half way down is "Food for thought: Forward and reverse
power". If you're not interested in the math, scroll down a few
paragraphs from there to the table in Courier font. It and the text
below explain how it shows where the source dissipation is higher,
lower, and about the same when the load is matched, for three different
loads all having the same "reverse power". Another entry in the table is
an example where the "reverse power" equals the forward power (an
infinite SWR) yet the source dissipation is zero. People who believe
that "reflected power" ends up heating up the transmitter should take a
careful look at this, and see if they can explain it.

The established transmission line theory that's been well established
for over a century and that Ian, I, and countless others use daily for
solving real problems will, as shown in the example, tell us exactly how
much power is where and why. The "power is absorbed in the load" folks
can point to transmitters that get warm (sometimes) when working into
(some) mismatches. But they can never come up with a coherent reason for
the results shown in the essay table, or equations which will predict
just how much "reflected power" a transmitter will absorb and when. And
the reason is just as Ian said.

Unfortunately, some people, when presented clear evidence that the
concept is wrong, cling desperately to it nonetheless. For those,
explanations and evidence are a waste of time. But hopefully there are a
few readers out there who will see the problems in resolving their
theory with the evidence and redirect their thinking.

Roy Lewallen, W7EL