On Jun 12, 5:36*pm, Richard Clark wrote:
I see that I am going to have to re-assert your own standard:
On Fri, 11 Jun 2010 20:31:42 GMT, Owen Duffy wrote:
there is a proposition that a transmitter "designed/adjusted
for, and expecting a 50 + j 0 ohm load" can be well represented by a
Thevenin equivalent circuit and naturally has Zeq=50+j0.
On Sat, 12 Jun 2010 00:19:34 GMT, Owen Duffy wrote:
For the data I asked, you supplied:
I have performed many tests on many radios. One documented example is at
http://vk1od.net/blog/?p=1045.
and offered:
I invite you and others to perform the same test. You will realise that
one, or even 100 supporting tests do not prove the proposition, but one
valid test to the contrary is damaging.
The test of proving the "proposition" invalid is, in part:
Adjusting the load impedance ... on this load with VSWR(50)=1.5
... is proof that the equivalent source impedance of the transmitter is not *50+j0Ohm.
I observed how you violated the adjusted-for part of
"designed/adjusted for, and expecting a 50 + j 0 ohm load."
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."
*******
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,
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.
that assumes the source is linear... with a non-linear source it is
much more complicated to describe the full range of it's response.
you would have to do a series of output voltage vs current curves for
a range of impedances.