| 摘要 |
PURPOSE:To improve the utilizing efficiency of a transmission line in transmitting voice and data through a high speed digital transmission line by switching the system into low speed communication and comparatively high speed communication while being connected to a conventional multiplex device. CONSTITUTION:A multiplexer 20 is provided with a switch 21, through which a voice interface circuit 6 and a data interface circuit 12 are connected to a multiplex device 7. Thus, 5 data terminal lines are connected to a multiplex means at day, for example, and the communication speed is suppressed to 12.8kbps to multiplex the five lines into one relay line. Then the remaining relay lines are all used for voice during the period of said connection state. Thus, the five data terminal lines are disconnected from the multiplex means, e.g., at night, and connected one to one to the relay lines, only one relay line is assigned to voice applications and many data are transmitted at high speed. |
