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Walter Maxwell · June 18th 08, 04:59 PM posted to rec.radio.amateur.antenna

"Richard Clark" wrote in message
news

On Wed, 18 Jun 2008 03:39:54 -0500, (Richard
Harrison) wrote:

The question of "what is the source impedance" presented to a load by
the amplifier? is answered, not by magic, but by the maximum power
transfer theorem. The amplifier must be adjusted to deliver all its
available power. Then, the output impedance of the amplifier is simply
the conjugate of the load impedance which is easily measured.

Hi Richard,

MPT Conjugate Match Z Match

You can NOT achieve the COMBINATION of any two, much less all three
with a Class C amplifier. This is like checking all three possible
answers on a multiple choice exam. It follows that source impedance
has not been answered here as a qualifiable (which is certainly not
what I was looking for).

I will take it that you don't know what the source impedance is as a
quantifiable either. That is, unless you unwind all the confounding
statements and remove those in error. There cannot be three,
simultaneous quantifiables of differing values.

73's
Richard Clark, KB7QHC

Hi Richard C,

Am I hearing you correctly? Are you disagreeing with Richard H? Are you saying
that maximum power transfer, conjugate match at the output, and Z match cannot
occur simultaneously? Are you serious? As I understand Everitt's statement of
the maximum-power-transfer theorem, when the maximum available power is being
transferred to the load there is a conjugate match. Does this not also mean
there is a 'Z' match? Can't 'Z' be assumed to be the impedance of the source as
well as the load?

Walt, W2DU