Circuit for a central control time division multiplex pcm telecommunications system with groups of terminals connected to a switching network

Abstract From the Canadian patent

A circuit for a central control TDM PCM telecommunications exchange with groups of terminals connected to a switching network is disclosed in which the terminal groups which are each connected to the duplicated switching network over TDM lines and which each include a subsidiary switching network and a decentral control unit are assigned to one another in pairs. In preparation for the stand-by substitution of the central switching network and associated central processor, in the two terminal groups assigned, to one another in pairs, the subscriber lines and/or connection lines connected to the first of said terminal groups can be switched-over from the subsidiary switching network of the …