| 摘要 |
PURPOSE:To facilitate an easy connection of a channel board when the number of channels is increased and to improve the maintainability by designating a up or down circuit according to the connecting position of the channel board, therefore making the occurrence of a channel setting error difficult. CONSTITUTION:Common parts 11 and 12 are connected to up and down PCM circuits respectively, and the signals related to channels needed by own station are transmitted and received with the PCM circuits. The undesired signals related to channels are sent to both PCM circuits. The exclusive up channel means CHP1(A)-CHP3(A) are provided at the part 11 and a termination equipment 6, and transmission/reception is carried out for the channels needed by own station. While the exclusive down channel means CHP1(B)-CHP3(B) are provided between the equipment 6 and the part 12. These exclusive channel means have plural channel parts and allot independently the minimum necessary own channel parts. Then a wired OR connection is devised between the rest channel parts and the equipment 6 corresponding to numbers opposite to each other to use the channels by the up or down PCM circuit. Then the wired OR output is led to the equipment 6. |
