Switching system for telephone network - has subscriber input points connected to local controls, in turn connected to central unit

摘要

The switching system is designed for a centrally controlled telephone network. The network has one or several switching panels with points for exterior connections. The subscriber input points are, each time, connected to a local control which has access to a coupling panel. The coupling panel and the local control are also connected to the central control unit. The local control regulates the exchange of data between the subscriber input point and the central control unit. According to the sense of exterior connection, the selection data chosen in the subscriber input point is transmitted in one of two ways. Firstly, it may be transmitted into the local control and emitted after the process of selection used for exterior calls on to the exterior line. Secondly, it may be transmitted without change from the local control to the central control unit.