GB1278372A - Improvements in or relating to telecommunication systems - Google Patents

Abstract

1278372 Automatic exchange systems SIEMENS AG 24 July 1970 [25 July 1969] 35920/70 Heading H4K In an exchange having a plurality of concentrators each connected thereto by a smaller number of links than there are subscribers lines terminated at the concentrators, a plurality of concentrator control units are provided, these being connectible as desired to any concentrator via the exchange's speech switching network. The latter KF has subscribers T1, T2, T4 and concentrators KZ1, KZ2 connected to its inlets and local junctors VO, trunk junctors VF, registers R, internal junctors JV and concentrator controllers KS connected to its outlets, the whole arrangement being centrally controlled by Z. When a concentrator subscriber is calling, an indication of this fact is detected by devices A which call in Z whereby a free controller is allotted and then connected via KF and a predetermined link, e.g. the one currently supplying power, to the calling subscriber's concentrator. The controller determines the identity of the calling party who then dials the wanted number into a register or the already seized controller if this is equipped for digit reception. Armed with calling and called party identification the central control takes over the call and the controller and switch path thereto are released. On an incoming call, recognition of a concentrator subscriber results in Z seizing a controller and connecting it to the relevant concentrator. The wanted subscriber is tested by the controller and if he is free a path is cut through KF (by Z) from the incoming junctor to the already seized concentrator link, the controller meanwhile being released.