Richard Clark wrote in
:

....
I observed how you violated the adjusted-for part of
"designed/adjusted for, and expecting a 50 + j 0 ohm load."

The IC7000 has no relevant user adjustments, it is designed for and
adjusted for in its design, manufacture, and alignment.


As no claim has been made by anyone about a source being constant in Z
nor in Power across all loads and all frequencies, your response does
not conform to your own reprise of the "proposition."

To be usable, any pretence of linearity at least over a limited range of
loads, power, frequency, Zeq must be sufficiently constant within that
range.

What you have performed is a load pull which constructs a curve of
complex source impedances around the point at which the transmitter
was adjusted for a 50 Ohm load. All well and good. However,

No, I have performed a go/nogo test on whether the transmitter delivers
sufficiently constant forward power into a quite limited range of loads.
The meaning of "sufficiently" is proposed in the reference article
describing the test and providing the mathematical basis for the test.

Thevenin's theorem says nothing of this. The correct test, to the
letter of the theorem is a test no one performs: the measured open
circuit voltage divided by the measured short circuit current.

No, Thevenin's theorem does not speak at all of how to test a source. For
a linear source, your proposed test of o/c voltage and s/c current would
provide sufficient data, as would ANY two points on the (complex) v/i
relationship.

I expect that a typical HF ham transmitter output is not linear over the
entire v/i characteristic, but my test just focuses on whether it is
approximately linear over a limited range of loads.

My recollection of Walt's tests were that they tested at points other
than Zl=0 and Zl=infinity.


*******

If I were to return to another statement from your link offered in my
quote above:
the transmitter is 50+j0Ohm
is in all likelihood incorrect. I am speaking strictly to what is
reported and to the implied accuracy of 50 ±0.5 Ohms. I seriously
doubt that you have the means to achieve the absolute accuracy of 1%.

You dwell at some further length on the implicit accuracy of the stated
quantity, but ignore the explicit discussion about a reasonable tolerance
for the test.

Owen