Patent GB-665343-A (GB)
Title: Receiving and transmitting device for printing telegraphic singals
IPC: H04L12/00
Filed: 1947-10-23
Abstract: 665,343. Telephone exchange systems. STANDARD TELEPHONES & CABLES, Ltd. Oct. 23, 1947 [July 26. 1946], No. 28328/47. Class 40 (iii). A register for electrical signals each consisting of code signal elements and start and stop elements comprises groups of electrical storage devices, one group per signal, for recording the code elements of a series of received signals, a distributer arrangement actuated by the start element of a signal to distribute the code elements of said signal over the devices of the first group of devices and switch. ing means actuated by the stop element of said signal to switch said distributer from said first group of devices to a second of said groups of devices. The start impulse on the incoming line IL operates relay R1 so that a timing device S operates relays Fr and Gr for periods corresponding to half the length of the signal elements. Relay Sta is normally operated over line M, back contact of Gr and back contacts of relays 1x ... 5x and Stax. When relay Gr operates, Stax is operated in series with relay Sta over a back contact of relay 1x. When during the start element relay Gr releases, a circuit is completed for relay 1. During the first code element relay Gr is operated and a circuit is completed for relays 1, 1x in series, and if the code element is a mark, a circuit is completed over the armature of relay Fr to a relay A which on operation effects the actuation of a relay A1 in the first group of storage relays A1, B1 ... E1. Similar operations are performed by the relays 2, 2x, 3, 3x ... of the counting circuit and when the fifth signal element is received, the release of relay Gr operates relay Sto. When Gr is operated during the stop element, Sto and Stox are operated in series and over a back contact of Stox and back contact of relay Ir a relay Hr is operated to transfer connections from some of the relays A1, B1, C1, D1, E1 to corresponding members of the second group of relays A2, B2, C2, D2, E2, which are not shown. During the start impulse of the second signal, relays Sto, Stox are released, and relay Ir is operated over the operated contacts of Hr to complete the transfer of the connections. The selective operation of the relays A1, B1 ... mark correspondingly the terminals a1, b1, c1 ... and in addition are arranged to connect a lead J1 to a terminal U1, 0 ... 9 represented by the fiveunit code signal received. At the end of the fourth signal, relay Xr is operated and with Yr operated at the beginning of the fifth signal, the code elements of the fifth signal are stored on the relays A5 ... E5 with corresponding markings of the terminal a5 ... e5 and connection of the lead J5 to one of the terminals U5, 0 ... 9. When Stox is operated, relay Zr is operated and removes earth from line M so that further signals are ineffective. The stored signal may be transmitted as a five-unit signal over a line to another exchange or, as converted to signals on a decimal basis, may operate local selectors to establish a connection to a subscriber of that exchange. Retransmission of signals or operation of exchange selectors. The line T, Fig. 5, leading to a further exchange terminates in a contact member operated by a relay T1 and the receiving line R terminates in a relay SR which is operated when the distant exchange is free to receive signals. Earth applied over the line H1, operated contact of relay SR, released contact of relay Mr and unoperated contact of relay Kr operates a timing device S2, which pulses relays Eir and T2 similarly to the operation of relays Fr, Gr by the device S1 of Fig. 2. The initial operation of T2 removes a shortcircuit from T1 which operates over a circuit from the back contact of Eax and operated contact relay Ea to effect the transmission of the start impulse from the operated contact of relay T1. The counting chain Ea, Eax, E1, E1x ... E5, E5x, and Eo, Eox operates in a manner similar to the relays Sta, Stax 1, 1x ... of Fig. 2 so that the impulses stored in the terminals a1, b1 ... are transmitted over the line T. The operation of E5x operates a relay Nr and when E5x releases during the stop element, Mr is operated in series with Nr so that the terminals a2, b2 ... (not shown) are connected to the counting chain operated by the timing device S2. At the end of the fourth signal relays Tr and Ur are operated. At the end of the fifth signal Vr operates and effects release of the receiving circuits. If the signal is to control the selectors of the exchange, one or more of the received characters is/are arranged to operate a relay Kr so that earth over the line H1 is applied to a line leading to the first selector switch. When it reaches the marked terminal corresponding to the first numeral it operates relay Lr momentarily so that relay Nr is operated and when relay Lr releases relay Mr is operated so that earth on H2 (not shown) is applied by a relay corresponding to Hr to a second selector which is stepped until it reaches the marked terminal U2, 0 ... 9 (not shown). At the end of.the selection Vr is operated and releases the receiving circuits. The relays which are normally of the telephone or telegraph type may be replaced by electronic devices, and the signals repeated may be other than those having a numerical interpretation or equivalent.