短距离同线呼叫系统

Exchange system on one line of communication in short distance

在总长度不超过1000m一条线路上通过被呼电路最多连接128个电话机,由转接主机控制相互呼叫.当线路超过300m时,转接主机应放在线路的中间.线路在500m内线径用0 35mm,否则用0 51mm的铜线.

The called circuit may be in connection with 128 subscribers at most in a line, of which the total length is not more than 1 000?m.The call each other is in the charge of the host computer of switching. In case of the lines total length is more than 300?m, the host computer of switching should be in the middle position of the line. 500?m lines internal diameter should be 0.35?mm, otherwise should be 0.51?mm.