Richard Clark wrote:
Hi Tom,
It's not that difficult. Edison corrupted the Thevenin model
demanding that there be a RESISTANCE equal to the load to accomplish
this equivalency (a case of being overly literal for a market
advantage). The Thevenin model only requires an IMPEDANCE, hence
these allusions to 50% maximum efficiency (an imposed condition much
like debate here) were an invention by Edison to detract investment
away from AC power transmission and attract it back to his DC dynamos.
The real pro's new how to dance with numbers and concepts too.
This resolves how the common Ham rig can present 50 Ohms Impedance and
still offer more than 50% efficiency - although, a simple examination
of the power in vs. the power out reveals it isn't nearly as good as
50% for ANY mode. Such is the gulf between reality and theory - some
folk's mileage may vary. ;-)
73's
Richard Clark, KB7QHC
Understood. I still want to find it. Been about 30 years since I wrote
it all down in 4 colors. I took serious notes.
tom
K0TAR
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