Roger D. Johnson wrote:
>
>Just to make sure I was correct, I looked up conjugate match in one of
>my textbooks. A
>conjugate match exists when reactances are cancelled and the resistance
>of the load is
>matched to the internal resistance of the generator. Under these
>conditions, the power
>transfer is maximum. However, since the resistance of the load and
>generator are made
>equal, the same power is dissipated in both thereby limiting the
>efficiency to 50%. If your
>amp is over 50% efficient, then it can't possibly be conjugately
>matched. As I stated earlier,
>we don't design amps for maximum power out. We design for desired power
>out whilst
>keeping the tube in the linear portion of it's operating range.
Roger, doggone it, you are correct!
I remember people (I think it was Dick Erhorn) telling me this once
before. Yes, maximum efficiency is not the point of maximum power
transfer. Every design has its tradeoffs.
Thanks for the point.
73,
Jon
KE9NA
-------------------------------------
Jon Ogden
KE9NA
http://www.qsl.net/ke9na <--- CHECK IT OUT! It's been updated!!!!!
"A life lived in fear is a life half lived."
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