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Re: [Amps] again

To: "'R L Measures'" <r@somis.org>, "'Tom W8JI'" <w8ji@w8ji.com>
Subject: Re: [Amps] again
From: "Joe Subich, W4TV" <w4tv@subich.com>
Date: Mon, 3 Jul 2006 10:20:28 -0400
List-post: <mailto:amps@contesting.com>
Rich wrote: 

> > The conjugate match theorem tells us nothing about what goes
> > on inside the source, never has...never will. The rules or
> > limits of the theorem  even state that.
> > Anyone who thinks a match to the source means 50% efficiency
> > apparently haven't read the theorem or can't understand what
> > the model represents. All it represents is maximum power
> > transfer. Nothing more.
> 
> In one of my electronics classes, the professor proved conclusively  
> that maximum power transfer occurred at 50% efficiency, but I see  
> amplifiers that exhibit 60% efficiency.  Please explain why, Tom.  tnx

Although I have not done the mathematics, since power transfer 
occurs at less than 360 degrees when the amplifier is operated 
in other than class A service, why don't you try doing an integration 
of the power/efficiency while the tube is in conduction (actually 
delivering power to the tank circuit)?  I suspect you might find 
a roughly 50% efficiency during the "power pulse" and what is 
measured by amateur methods is an average over time further modified 
by failure to account for the "feed through power" in common grid 
circuits. 

73, 

   ... Joe, W4TV 
  

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