Patent GB-1062215-A (GB)
Title: Improvements in or relating to time-division multiplex telecommunications systems
IPC: H04Q11/04
Filed: 1963-09-02
Abstract: 1,062,215. Automatic exchange systems. SIEMENS & HALSKE A.G. Sept. 2, 1963 [Sept. 4, 1962], No. 34530/63. Heading H4K. In a time division multiplex system break-in facilities are provided through the use of speech energy stores, which transfer speed energy from one pulse position to another. As described an existing connection between subscribers N2 and Nx using pulse position P10 is effected by the presence of the respective addresses in circulating stores Ua, Ub and a further subscriber N1 using pulse phase P1 breaks in. The speech energy stores have a circulating store Us for storing their addresses and one of these energy stores is seized and its address is inserted in Us in both phases P1 and P10, thereby effecting connection of the speech energy store to the speech multiplex highway at both P1 and P10, so enabling transfer of speech energy between the phases so that N1 can break in on the conversation between N2 and Nx. First embodiment, Fig. 1.-Assume subscriber N1 attempts to call N2 who is busy, in a call to subscriber Nx using pulse position P10, pulse phase P1 having been allotted to N1 for this attempt. Then P1 is present in the combination of delay lines in Ua indicative of the calling subscriber. P1 is also in the switchthrough store Uda. P1 is also present in Ub indicating the directory number of the wanted line. As the call has been unsuccessful P1 will not be in the switch through-store Ubd, but will be present in USi and emitted on lead bs indicating the busy condition. To initiate break-in the subscriber N1 operates a break-in key which causes, by means, not shown, the seizure of a digits receiver Zex which signals the break-in condition via Z to lead qs to bring up trigger SQ. As AZ steps, AA emits pulses over a/va used by the various subscribers indicated by AZ, so that when AZ indicates N1, P1 is emitted to G4 which also receives indications from the other stores that P1 relates to an unsuccessful call, and thus operates trigger X1. P1 is also stored in delay line APh. With SQ up, Y1 follows so that during the next (operation) cycle, G9 emits P1 received from APh for storage in store UQ and sequence counter QZ is stopped to position 1. During information cycles, ZS, which emits cyclically the addresses of storage devices ESS1 ... X, tests whether the address emitted is free and if so during the succeeding operation cycle energizes lead s. This enables G12 to pass the P1 pulse stored in UQ to set X1, and Y2 operates in the succeeding operation cycle to open gate G16. Meanwhile, the P1 output over a/va has been stored in Aph and is then emitted via G16, whence it is inserted in Uds, and the address emitted by ZS is stored, via D4, in Us at this phase. This effects connection of the storage device ES1 (say) to the speech multiplex line SM at phase P1. QZ then moves to position 2. When AZ emits the identity of the wanted subscriber N2 then at P1 comparator RB emits a pulse which in combination with the pulse from UQ and Us and other relevant conditions sets X2. At P10 comparator AA emits a pulse (assuming that N2 is in Ua rather than Ub) and this condition amongst others sets X3, whereupon Y3 operates to cause a P10 pulse stored in delay line Zph to be inserted in store UQ. QZ moves to position 3. When ZS next indicates the seized storage device ES1 at P1, the UQ output coincides with that of comparator VS and these conditions amongst others bring up X4. At P10, the UQ pulse amongst others operates X5. The P10 pulse is also stored in Zph. Y4 then comes up to cause the stored P10 pulse to operate gate D4 to cause the ZS identity then present (i.e. that of ES1) to be inserted in Us at this phase, and the deletion of P10 from UQ. The P1 pulse from a/va stored in Aph is emitted by G32 (opened by Y4) to cause deletion of P1 in UQ. QZ goes to position 4 and thence to 5. When AZ next emits the identity of N1, at P1 gate G33 opens due inter alia to the output from comparator AA and a class-of-service break-in authorization from UM. P1 is also stored in APh. Trigger X6 operates followed by Y5 which causes G37 to emit the stored P1 pulse to erase P1 in the busy store USi and from store Ub which has been storing N2's identity at this phase. Q2 goes to position 6. When ZS again indicates the identity of ES1, at P1 coincidence, inter alia, of outputs from comparators AA, VS brings up X7. At P10, the output from VS inter alia brings up X8. Y6 then follows. P10 which has been stored in Zph is now emitted by G44 and stored in Vds. At P98, G46 emits a pulse to restore QZ. With the identity of storage device ES1 now stored in Us at P1 and P10, and with P1 and P10 both in Uds, gate ESS1 is opened at both these instants to connect the device to the multiplex highway SM. With subscriber N1 connected to this highway at P1 and the existing conversation being effected by this highway at P10, break-in is thus effected via the speed energy storage device ES1. Second embodiment, Fig. 2.-Initial conditions are assumed the same as in the first embodiment. A break-in request operates SQ as before. Seizure of a free storage device ES1 by the insertion of pulse P1 in Us takes place as in the previous example and QZ goes to position 1. With P1 in Vs, G54 operates XX2 followed by YY2 which causes G58 to emit P1 (stored in Aph) to cause the address of ES1 stored at this phase in Us to be transferred by gate D9 to the static register R, and the directory number of N2 present in Ub at this phase also is transferred via D6 to R where it is translated into the corresponding equipment number. QZ goes to position 2. At the next P10 pulse, comparison of the N2 address in Ua with that in R enables G59 to open and operate XX3 and, in the succeeding operation cycle, consequent operation of YY3 opens G64. Meanwhile, P10 from G59 has been stored in Zph and is now emitted by G64 to open D10 to cause the insertion of the speech store address at present in R, into Us at phase P10. The address in R is simultaneously erased and QZ goes to position 3. When AZ next emits the identity of N1, then at P1, comparator AA emits P1 which is gated by a break-in class-of-service condition derived from UM, and other relevant conditions at G65 to operate XX4 and YY4 follows. This causes P1 (stored in Aph) to be inserted in Us. QZ goes to position 4. When ZS next emits the identity of ES1 then comparator VS emits P10 which operates XX5 via gate G71. YY4 follows to cause the insertion of P10 (stored in Zph) into Uds. Storage device ES1 is now connected to the multiplex highway SM at P1 and P10 to cause break-in as in the first embodiment.