On Sat, 12 Jun 2010 19:52:15 GMT, Owen Duffy wrote:

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.

Hi Owen,

Well I see neither data of that Z over Loads over Power over
Frequency, nor do I read what you would call what is "usable."

The meaning of "sufficiently" is proposed in the reference article
describing the test and providing the mathematical basis for the test.

"Sufficiently" is a subjective term for which I see no objective
criteria.

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

Steps 1 and 2 are quite explicit.

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.

I see no further discussion of my observation of the possibility of 51
Ohms being, in your terms, "usable, sufficient, or reasonable," so I
dwell on what is known, and not on vacant adjectives.

73's
Richard Clark, KB7QHC