The termination of harmonic currents in a class-c amplifier

The performance of a low- frequency class-C amplifier was analyzed. A simple nonsaturating model was assumed. Power output, power gain, and collector efficiency were found to increase as the power supply voltage was increased. Collector efficiency increased and power output decreased as the conduction angle decreased. Not all collector voltage waveforms are possible with the classic (textbook) collector current if passive harmonic impedances are assumed. In particular, the square-wave collector voltage waveform is not possible. When the collector current waveform was assumed to be a rectangular wave, much greater fundamental output power was possible if the correct harmonic impedances were used. Collector efficiency was also improved. The study showed that the collector current waveform should be analyzed before the collector load is selected. Then harmonic impedances may be selected for best performance.