Observing transistor voltage waveform in high efficiency class-E HF/VHF/UHF power amplifiers

Class E amplifiers were introduced by the Sokals in the 70 s and, since then, numerous applications where higher efficiency was one of the key issues have seen the light. In this work a review of some useful and simple techniques to observe the collector/drain voltage waveform of the device was explained with examples. This work is really interesting for RF/MW high efficiency power amplifier designers because the included techniques can be directly extended to class D or class F.