Patent GB-1142947-A (GB)
Title: Improvements in or relating to automatic telephone systems
Inventor: BECKETT GILBERT JESSOP
IPC: H04M15/04
Filed: 1966-11-24
Abstract: 1,142,947. Automatic exchange systems. AUTOMATIC TELEPHONE & ELECTRIC CO. Ltd. 23 Nov., 1967 [24 Nov., 1966], No. 52702/66. Heading H4K. Statistical records are kept in a gateway exchange GWEX giving access to a national exchange network and switching incoming international traffic over bothway trunk circuits BWTR served by registers MF-REG and incoming national traffic over trunk circuits ICJRS served by registers LD-REG; routing across the exchange being governed by a router control (RCX, RCY) served by an international coder (ICX, ICY); call and switching data of incoming calls being recorded by way of an accumulator (ACX, ACY) and corresponding buffer store (ABSX, ABSY) for serial recording in a store (TPA, TPB, TPC); the timing of answer and release signals received by the trunk circuits being separately recorded by way of a store (ARSA, ARSB) which also registers the trunk identity as a means of collating call records from the interspersed serial records. The recorders TPA, TPB, TPC, are tape punchers connected by allotter TA. The exchange comprises one or more pairs of routers, RTRI (illustrated) and RTR2 (shown as an empty box). When a tape-puncher is allocated to a router it stays in the service of the router until it runs short of tape or is subject to fault when the spare one of the tape punchers stands in. For each pair of routers a separate punched tape equipment PTE is provided. The punched tape equipment has a 24 hour calendar clock CAL to time specific items of data by way of buffer store CK and to periodically (daily, hourly) date the tapes to facilitate identification for subsequent analysis and print-out. The exchange is of the kind described in Specification 1,003,404, the routes across the exchange being set up over X or Y sections according to whether a router control RCX or RCY has been seized for the call. Call data recording is initiated by forwarding a signal from the router control in use for the call to the associated address accumulator ACX or ACY which promptly registers the trunk number and the trunk group number. The accumulator interrogates the associated coder ICX or ICY to obtain a record of the country and area code of the wanted subscriber, the code indicating if the call is to be terminated at an operator's position, the language code, or code indicating if the route made available is first, second, or third choice, and a code indicating if the call has been set up successfully or has been frustrated by fault or congestion or has been abandoned before dialling is complete. Records may be confined to successfully completed calls. When calls from an international test centre are being processed the data identifying the incoming trunk circuit may be replaced by test characters if such records are taken at all. The address buffer store ABSX or ABSY offers the accumulated information to the allotted tape puncher as thirty sequential items of telegraph code including hour and minute codes drawn from CK. The clock is inhibited while time is being recorded and should a fault prolong the inhibition beyond 6 seconds a fault alarm is tripped. The answer and release buffer stores ARSA and ARSB serve one router and operate alternately to record the time of arrival of answer and release signals together with the identity of the relay set concerned. International traffic comes in over radio links or multi-channel carrier links over land or submarine cables.