The general oscillator theory pertinent to frequency stability is presented, and the superiority of the bridge oscillator is demonstrated. The tables provided show the similarity between the transfer functions, and certain other network functions, of the commonly used

oscillator networks. These networks are optimized for use in frequency stable oscillators, and some very simple constraints are found for the parallel-

network. Contrary to the ideas of previous authors the best network for an

oscillator cannot be established theoretically. Instead, it is shown that the seven networks given fall into only three groups. Together these groups provide a continuous range of the two major properties required for good frequency stability. These properties must be chosen empirically to match the amplifier used in a particular oscillator.