Abstract: An apparatus utilizing the basic oscillation characteristics of the Colpitts or Pierce and Hartley oscillator configurations. In this embodiment the basic shunt reactive shunt arms are replaced with a selected pair of tank circuits or one of the shunt arms with a series-parallel tank circuit.These tank circuits are tuned such that the sign of their effective reactances are the same between the range of resonant frequencies of the individual tank circuits or of the series and parallel resonant frequencies of the series-parallel tank. When this occurs and their sign differs from the sign of the effective reactance of the series reactive element, there is a 180.degree. signal phase shift in the feedback loop, and therefore oscillation.

Abstract: A method and apparatus for minimizing the noise component of the output signal from a resonator oscillator. A single transistor or Darlington pair of transistors in the common base configuration is placed in series with the crystal resonator of the oscillator with a selected output load impedance connected between the base and collector of the transistors. By making use of this configuration, it is possible to use the crystal resonator as an initial filter to minimize the noise component of the output signal contributed by the oscillator loop as well as minimizing the inherent noise component from the output buffer amplifiers in the output signal.