Patent GB-742249-A (GB)
Title: Improvements in or relating to arrangements for operatively connecting control apparatus with any one of a plurality of equipments
Inventor: THREADGOLD RONALD
IPC: H04Q3/42
Filed: 1952-07-09
Abstract: 742,249. Automatic exchange systems. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd. July 9, 1953 [July 9, 1952], No. 17271/52. Class 40 (4). [Also in Group XIX] In an arrangement for operatively connecting a control apparatus such as a translator with any one of a number of equipments such as registers, the control apparatus is arranged periodically to transmit a conditioning signal to all the equipments to initiate a hunting operation thereover, and the equipment requiring to be operatively connected with the control apparatus responds in such a manner that the first of the conditioned equipments reached is operatively connected exclusively with the control apparatus and the hunting operation is terminated. General description.-Dialling impulses are applied over lead 10 to the binary counter BC1-4, Fig. 1, in the register, Figs. 1-6, and stored as their complement to 15 in digit stores EDS1-3, NDS1-4, wherein they prime the appropriate tubes in transfer circuits EDT1-3 and NDT1-4. Transfer to the translator of the stored exchange digits over lines 1EDL-3EDL is effected by the arrival at the register of a sequential hunting pulse from the translator control circuit, Figs. 7, 8, which is itself controlled by a 400 C.P.S. oscillator, and the translation which is effected in the circuits, Figs. 9-12, results in the return of up to 6 digits each again as a complement of 15, to the. routing digit stores RDS1-6 over leads 1RDL-6RDL. The stored complements are applied successively to an outgoing counter DB1-4 and with each digit transferred, a dialling out multivrator DOM is started and impulses are sent to line DOL. The counter DB1-4 is also stepped by the multivibrator output so that after the complement to 15 of the stored complement, i.e. the digit from the translator, has been sent, the counter is returned to zero or normal. The multivibrator is then stopped. until it is re-operated by the next control pulse to send the next digit. At the end of the routing digit transmission, the digits in the number stores NDS1-4 are similarly transmitted to line. Detailed description. Registration of im. pulses. The register includes a relay group or its electronic equivalent which provides " A " pulses corresponding to the dialled impulses, " B pulses when the subscriber's loop is broken and " C " pulses when the register is seized and at the end of each train of " A " pulses. The tubes VK4 of counters BC1-4 are fired on receipt of the 1st C pulse and the " A " pulses are repeated to the first-binary pair VK2, VK3 by a self-extinguishing tube VK1. The first " A " pulse fires VK3, which is primed by a 50-volt source and VK3 in firing extinguishes VK4 and primes VK5. The succeeding pulse fires VK2, which was previously backed off by the potential across resistor R2, and VK5, the former extinguishes VK3 and the latter repeats a pulse to the succeeding stage wherein the valve corresponding to VK3 is fired. Succeeding pulses re-fire the described stages and fire the following stages according to the number of impulses in the received digit. The valves VK2 that are fired mark pulse repeaters PR4-7 and the marked pulse repeaters are fired by a " C " pulse applied over lead 12 at the end of the digit train. The same C pulse on lead 11 resets the counter. A digit counter 1CC1-7 is controlled by " C " pulses applied over lead 13 and its tubes conduct sequentially so that the marking on the pulse repeaters PR4-7 at the end of the chain of impulses appropriate to each received digit, is applied to its appropriate store EDS1-3, NDS1-4. The tubes ST1-4 in store EDS1 which are primed by 1CC1 fire when the marked pulse repeaters fire. When the second " C pulse steps the digit counting circuit to 1CC2 the cathode potential across 1CC1 is maintained long enough for storage in EDS1 to be effected, the appropriate transfer tubes TT1-4 in the digit transfer circuit being primed by such tubes as have fired in the store EDS1. Connection to translator. The " C " pulse reaching 1CC3 besides priming EDS3 primes 2CC1 of an outgoing digit counting chain and the " C " pulse after the registration of the last exchange digit fires 2CC1 to prime 2CC2. A recurrent pulse to all registers from the translator control circuit over lead SCR fires 2CC2 which primes 2CC3 and pulse repeater PR8 and fires diode VN1 to indicate to the translator control circuit over lead RQL that a register is awaiting connection to the translator. The pulse on lead SCR is produced in the control circuit, Figs. 7 and 8, by the first negative 400 C.P.S. pulse on lead 21 through valves VT10, VT11, VK48 and cathode follower VT12, and the second control pulse in firing tube VK49 initiates the sequential hunting for the waiting register by a pulse over leads HCR and HP1L to the first register. Tube VK6, Fig. 4, is fired if translation is not required and the pulse is passed to the next register over lead HP2L. This pulse is passed from register to register until the waiting register is reached, where it " backs-off " tube VK6 and fires outgoing counter tube 2CC3 and pulse repeater PR8. Tube 2CC3 in firing strikes the diode VN2 and applies a voltage over load RCL which indicates to the control circuit that a register is operatively connected to the translator. Translation. All the exchange digit transfer tubes TT1-4 in circuits EDT1-3 which have been, previously primed are fired and the cathode potentials are fed over leads 1EDL- 3EDL to decimal counters DCA, DCB, DCC, Fig. 9. These counters comprise four stages. The first stage comprises tubes VK70 and VK71 which are primed and backed-off respee. tively by a pulse over EDL1 and each valve in this stage and stages two and three are connected to a pair of valves in the succeeding stage which are similarly primed and backed-off by pulses on leads EDL2-4. The right-hand tube of each pair is initially primed and pulses over leads SAL and SBL from the control circuit mark one of the leads in each group of outlets DLA, DLB, DLC, according to the markings on leads EDL. Lead FTL gives a fault indication if no digit is displayed. The marked outlets in DLA and DLB corresponding to the first and second digit mark a single intersection of a hundred point field HPF of gas tubes VK111-210. These tubes are in ten rows of tens having their striking electrodes coupled to the ten counter outlets DLA through pulse repeaters VK91-100 and their anodes coupled to counter outlet DLB through tubes VK101-110 and their associated triodes such as VT14 and VT15. The tube in the hundred point field fired by the two digit markings, marks one of the leads TL1-100 feeding a thousand point field in which the horizontal rows are coupled to the outlets DLC1-10 of the counter DCC. In this arrangement there are six tubes at each intersection and each of the six tubes that fire as a result of the markings on leads TL and DLC draw current from a source HTL, Fig. 11, in a different one of the translation conversion units TC1-6 over leads RL and TFL. The potential drop across the appropriate resistor R10-19 in each unit fires a tube in one or more of the four ranks of tubes VK241-245, VK246-250, VK251-256 and VK257-263 through the appropriate pulse repeater VK231-240. The decimal marking on one of the ten leads TFL is thus converted to a binary marking on the four leads RDL. The cathode followers VT17-20 which repeat the pulses on the fired tubes in the ranks fire by way of lead TCL diodes VN10-13 to indicate to the control circuit that translation has been completed. Tube VK61 is primed and VK62 is backed-off when the diodes strike, and when VK57 is fired by the next 400 C.P.S. control pulse tube VK61 fires and indicates the end of translation to the calling register by stepping the outgoing counter to 2CC4. The priming voltage applied to the routing digit storage circuits by 2CC3 is maintained whilst the pulses applied over leads 1-6 RDL fire the corresponding tubes in each store and the digits, indicated by unfired tubes, are passed to translation transfer tubes TT29-32. Sending. A pulse over lead SDL to repeater PR45 indicates the completion of the connection to the outgoing junction and the repeated pulse fires pulse repeater PR9 to transfer the digit from store RDS1 to dialling-out binary counter DB1-4 which is similar to counter BC1-4, through pulse repeaters PR11-13. Tubes VK9 are fired when H.T. is switched on and are extinguished by the fall of potential across the common anode resistor R4 when transfer takes place and VK8 fires. The fired tubes VK9 collectively indicate the translated digit, i.e. the complement stored in RDS1 is converted. The pulse from repeater PR45 also fires tube VK10 in a stored digit test circuit TSD and after a delay diode VN4 strikes and fires tube VK11 which extinguishes tube VK10. A pulse from diode VN4 is also applied to tubes PR14 and PR15 which are oppositely controlled by resistors R5 in the counter circuits, i.e. PR14 is primed and PR15 is backed-off. If the register is ready to send over the exchange junction PR14 fires, and fires VK12 in a dialling-out start circuit DOS, which in turn starts a dialling-out multivibrator DOM sending impulses over lead DOL. After each impulse the counter DB1 is stepped by a pulse from tube VT1 which is applied via PR16 to the binary pair in DB1 and PR11. PB16 also repeats the same pulse to a test circuit TED via a delay network EDC. TED is similar to PR 15 and is controlled by the potential across R7, and the multivibrator is stopped by the firing of tube VK13 by the last pulse applied to TED when all the-valves VN5 are extinguished. The pulse from TED resets valves VK9 of circuits DB1-4 and transfers the pulses from the second store after the correct inter-digital pause via circuit 1DP, repeaters PR17 and 18CP, test circuit TSD, and repeater PR19 which steps the outgoing counter from 2CC5-2CC6 (not shown). The same sequence is followed for each digit transferred and the outgoing cou