Complex deviation of bridge oscillators

It is shown that the real part of the complex deviation defined in this paper for bridge oscillators is related to the amplitude stabilisation, and the imaginary part to the frequency stabilisation, in the oscillator. Complex deviation is computed as a function of amplifier gain and phase and output power. With the aid of complex deviation, overall performance of different bridge oscillators is readily compared. A simple single-transistor/ferrite bridge-oscillator circuit is given with frequency deviation within 10¿4 and amplitude stability within 1 %.