Hello Tim,

Look for class E. Class D describes an amplifier that switches faster
than the signal and has the output filtered to pass DC. Class E
describes an amplifier that switches _at_ the signal rate and has a
filter that has finite impedance at the fundamental and infinite
impedance at all the odd harmonics. The result is that the output
transistor drives a square-wave voltage and sees a sinusoidal current,
so all the power goes to the output with none wasted.

There have been articles in QEX and even QST -- they even explain what
I just said in sufficient detail to understand it.


Thanks for the information and article links.

I have some articles fromm Sokal and Raab on E. Also familiar with Steve
Coultier's class-E web site.

I have a QEX/QST compilation CD somewhere.

Do you have any month/year references to hand?

Tnx

--
Philip de Cadenet G4ZOW