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Old February 26th 05, 01:26 AM
Tom Ring
 
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Ken Smith wrote:

In article , gwhite wrote:

Ken Smith wrote:

RF transmitter power amps are certainly "impedance matched" to the
intended load.


I'm sorry, but they are not. Nor are any power amps that I know of. Efficiency
(and thus necessarily output swing) is what matters for power amps. To maximize
swing requires load line matching, not impedance matching.



I still say they are. Motorola AN-721 takes on the theory. AN-758 does a
practical example matching 12.5 Ohms into 50 Ohms



Sure are. A 30 year ago 500 level course I took called Non-Linear
Transistor Design said so. The way you handle class C etc. is by
handling each harmonic separately in your analysis of the transistor
plus tank circuit. You match to the harmonic you want. It may be the
fundamental, or the third for a tripler, etc.

tom
K0TAR