Hero999 said:There is nothing wrong with my class C scematic a diode is often used, it does help to control the duty cyle.
A resistor should still be connected between base and emitter, the diode is more likely there more as a protection measure than anything else? - in case the stage is fed with a high signal level (to prevent reverse Vbe breakdown - which occurs about -7V to -9V). If anything it will reduce the generation of harmonics, as it will tend to slow down the switch off speed of the transistor.