Abstract: In radio communication system using angular modulation, the presence and quantity of cochannel interference is detected. According to the invention, when desired signal and undesired signal are received simultaneously, an envelope of the received IF output signal involves low frequency spectrum component similar to that of fading and high frequency spectrum component with several KHz. The low frequency spectrum component and high frequency spectrum component are then calculated, and the interference ratio D/U is obtained by processing said components.

Abstract: An hydraulic transmission interposed between an engine and the wheels of a vehicle is controlled by hydraulic circuits and hydraulically-operated clutches. A shift valve assembly is supplied with oil pressure in accordance with the extent of opening of the throttle of the engine, as well as vehicle governor pressure acting as a vehicle speed signal. The shift valve assembly not only functions to control operation of hydraulic clutches but also acts as a malfunction-preventive valve which operates to impede engagement of the reverse transmission clutch during forward running of the vehicle at a speed higher than a predetermined vehicle speed, irrespective of the throttle valve opening.

Abstract: A fire prevention device for a fixing stage of an electrophotographic copying machine includes a heat shield plate movable to close the fixing stage. The heat shield plate may be controlled by a control mechanism having first and second solenoids so that the heat shield plate shuts the fixing stage only when a driving power for the copying machine is stopped or an abnormality is detected in a fixing step, during the copying operation.