Hi Reg,
To understand that simulation, try looking at some of the transistor models that get used.? ? ? As perhaps you surmised, class C is about they output and not about the input.? ?But, you confusion is with the input, so let's look at the base to emitter circuit for a simple? transistor model.? ?One simple transistor model would have a resistance and a 0.6V battery between the base and emitter pins without any feedback from the collector to emitter.? ?So, a sinusoidal input would have a sinusoidal current waveform, but not have any feedback from the output.
More complex transistor models such as those used by spice do have feedback from the output.? ? I would say that diagrams in 9A, if generated with Spice, probably aren't perfect sine waves.? You just can't see the distortion because it is low.? ?The reflection coefficient should give you an idea of how big this feedback is.? If you're looking at Bowick, look at pages 98-102 where he talks about the transistor model, and especially the section on input impedance.? ??
73's Jim N8CAH
