Abstract: A noise control system for an FM stereo radio receiver is provided for controlling noise in the audio output, particularly in an area where the broadcast signal strength is relatively high. The system is designed for use with an FM stereo radio receiver having circuitry responsive to the strength of the broadcast radio signal for reducing stereo channel separation and/or high frequency response in low signal strength areas to prevent deterioration in the signal/noise ratio. The system includes a detection and control circuit for detecting the presence of relatively high noise levels substantially independent of the broadcast signal strength, such as multipath distortion encountered by a radio receiver in a vehicle moving through a high signal strength area. The detection and control circuit operates, in the presence of detected high noise levels, to control the adjustment circuitry to reduce channel separation and/or frequency response and thereby reduce the noise in the audio output.

Abstract: A system is provided for controlling the mode of operation of a combination radio/tape player unit, particularly of the type commonly installed in vehicles and including a mode control switch for automatically switching the unit from a "radio" mode to a "tape" mode upon insertion of a tape cassette or the like into the unit. The mode control system comprises a mode override switch responsive to operation of the unit in a fast-forward or reverse condition for rapid advancing or rewinding of recording tape to return the unit to the "radio" mode for the duration of the fast-forward or rewind operation.