A bilateral transistor detector∗ for demodulation of an FM stereophonic signal

A balanced detector circuit of improved efficiency for demodulation of an FM stereophonic signal using a single bilateral transistor is discussed. The detector has the feature of an equal level circuit for stereophonic and monaural reception. It is shown that a slight modification from the ideal case makes it possible to accommodate large variations in the forward and reverse characteristics of the transistor such that an inexpensive alloy junction transistor can be used. Matrixing is achieved by an in-phase composite stereo signal which does not require a phase inverter. Performance data are given.