Design Considerations in the Development of High Quality Stereo Multiplex Receivers with Integral Multiplex Circuits and a ``Multiplexer´´ for Use with Monaural FM Receivers

General requirements of the FM stereo receiver are reviewed with emphasis on high quality stereo performance commensurate with the system capability. In the commercially manufactured receivers described, proper attention has been given to each of these requirements, and the stereo demodulation circuits are integrated within the radio chassis. Two approaches are covered; one, a complete self-contained stereo FM radio, and the other, a novel solution to the conversion problem for existing FM receivers. The latter consists of a ``Multiplexer´´ receiver which is not an ``adaptor´´ and which requires no connection to the monaural receiver. Circuit details and performance data are included.