| 摘要 |
PURPOSE:To make a special monitor trunk and an exchange terminal for storing it unnecessary to simplify the constitution, by leading in all channels of a digital multiple line and by-passing them to designate an optional channel. CONSTITUTION:In case that the digital signal on an optional channel of a digital multiple line 5 is monitored, a central controller instructs an interface 4, which is connected to the digital multiple line 5 (a corresponding outgoing line 3) including the channel to be monitored, to split the digital multiple line 5 and the outgoing line 3. On a basis of this instruction, the designated interface device 4 splits the digital multiple line 5 and the outgoing line 3 simultaneously and leads channels into an interface device test module 9 by a leading-in line 8. The interface device test module 9 by-passes all led-in channels by the instruction of the central controller and mixes digital signals in the transmission side and the reception side of the disignated channel, and these signals are converted to analog signals and are outputted. |
