| 摘要 |
PURPOSE:To set the interference noise caused by a shift of frequency of a clock signal at a level higher than the audible frequency and to eliminate the beat sound of a mobile radio, by making the clock signals of transmitting circuits to have different frequencies and at the same time decoding the PCM code with the different clock. CONSTITUTION:The PCM signal is transmitted via the same transmission line 100 among plural multiplex transmitting circuits by means of the clock signal given from a clock signal generator 3a provided to each transmitting circuit. In such case, the signal supplied through a line 100 is detected by the edge and level detecting circuits 21 and 22 of a receiving unit 20. The clock of the generator 3a is replaced with another clock by a frequency divider 7a and synchronously with the signal detected through the circuit 21. The replaced clock signal is applied to the circuit 20 and a data information detecting circuit 23. The different frequencies are set for the clock signals of transmitting circuits, and the PCM code is decoded by the different clock signal through the circuit 23 and a data decoding circuit 24. Thus the interference noises due to a shift of frequency of the clock signal is set at a level higher the audible frequency. |
