On Apr 12, 8:15 am, Cecil Moore wrote:
I have told you many times. Bench test measurements
performed over the past 20 years or so prove that it
works only in your mind, not in reality. The source
impedance of a typical ham transmitter remains somewhat
of a mystery during actual operation. The arguments
continue to rage after decades of bench test experiments
and measurements. The pages of QEX are filled with those
arguments.

So your only beef with my examples is that they do not
accurately model a "typical ham transmitter"?

A generator with a 450 Ohm source impedance ...

False assumption. That transmitters's source impedance
changes away from 450 ohms just as soon as the reflections
arrive incident upon the source, i.e. the source impedance
is a *variable* that depends upon the magnitude and phase
of the reflected wave.

When you say that source impedance is a "variable", do you
mean this for a "typical ham transmitter", or do you assert
that it applies to every generator, even those which can be
accurately modelled with a Thevenin equivalent circuit (as
many signal generators, even TVSGs can)?

I think you object to computing the amount of the reverse wave
that is reflected at the generator by using the source impedance.

I certainly don't object to your computations but the
results of those computations have been disproved on
the bench using real world ham transmitters over the
past 20 years or so.

Which results have been disproved on the bench?

Your simple mental model doesn't
correspond to reality unless you take some extraordinary
steps which deviate from real-world ham transmitters.
Have you taken the time to review those experiments?

Are the experiments documented in Reflections chapter 19 and
19a representative examples?

My read of these chapters is that they offer compelling
argument and evidence (at least for the tube style
transmitters examined) that ham transmitters are linear*,
at least over their normal region of operation.

Is it your assertion that these claims are incorrect?

....Keith

* Don't confuse this use of linear, which is that the
output stage is linear, with whether the input to output
transfer function of the transmitter is linear. The transfer
function may be non-linear even though the output stage is.