CW and PSK can use class-E?

Hi,
CW can use class-E amplifiers and does not require linear ones, since only the carrier is switched on/off.

Is that also the case with PSK, where the carrier changed phase, or does PSK require linear amps?

PSK is usually NOT constant envelope. Think of a BPSK signal, when it goes from zero to 180 degrees....the signal has to go thru the origin...i.e. momentarily it has zero amplitude, especially if there is any sort of bandpass filter in the path. So passing it thru a non linear amp will have degradation.

You could try it and see if the degradation causes too many bit errors in your application.

Thanks a lot