A class-C loop gain amplitude modulator

A class-C loop-gain amplitude modulator is described. The class-C loop gain circuit not only produces the characteristic high degree of modulation linearity, but also allows the modulating signal to be applied to the base circuit of the transistor modulator. Along with small modulation source current, very small modulation voltages are required to achieve large carrier amplitude deviations. This reduces the modulating source power by two or three orders of magnitude over the traditional collector modulation stage. Excellent modulation linearity is exhibited while only a very low level of modulating source power is required.< >