Phase stabilization to microwave frequency standards

An improved circuit for phase stabilization of a klystron oscillator to a microwave frequency standard (e.g., a maser oscillator or harmonics of a crystal oscillator) has been developed. Phase detection at a high level using IF transformers insulated for the klystron reflector voltage makes a floating amplifier unnecessary, and the use of an integrating filter makes it possible to maintain stabilization for relatively slow frequency deviations of the klystron (due to thermal drift, power supply variations and microphonic noise) up to mc. No acoustic isolation or extreme power supply stability is required, and the stabilized oscillator will track a frequency modulated signal. A number of stabilizing system are proposed by which a microwave oscillator is stabilized in synchronism with a microwave reference signal, offset by an intermediate frequency, or swept through the reference frequency. A stabilized variable frequency oscillator and tracking narrow band reciever is proposed for use in microwave spectroscopy.