Patent GB-833811-A (GB)
Title: Electronic teleprinter
IPC: H04L25/45
Filed: 1957-08-02
Abstract: 833,811. Type-printing telegraphy. SOURGENS, R., and CHOLLET, R. Aug. 2, 1957 [Aug. 2, 1956], No. 24504/57. Class 40 (3). An electronic transistor-controlled teleprinter apparatus for receiving a transmitting startstop telegraph signals having u information code elements comprises a receiver trigger device connected to the input lead of a telegraph line, a keyboard with keys effecting the setting of u transmission element contacts and a universal contact, and a transmitting trigger device connected to the output lead of the line, a time-base constituted by an oscillator with a plurality of cascade-connected binary frequency dividers connected to a matrix providing timing pulses on a set of conductors and set into operation by the triggering of said receiver trigger device or by the universal contact of the transmitter, a plurality of n gate circuits connected to the matrix conductors and controlled by the receiver trigger device or the universal contact and a plurality of n binary storage circuits having their inputs connected to the n gate circuits and to the n transmitting contacts and their outputs connected both to the output trigger device and to a plurality of receiving code electromagnets and a correction or adjustment circuit associated with the timebase and connected between one of the matrix conductors and one of the frequency dividers and operating to reduce the cycle of the timebase from n+2.5 element time intervals when the teleprinter apparatus is transmitting to n+1.5 element time intervals when the teleprinter apparatus is receiving, and the teleprinter apparatus also includes a transmissionreception trigger circuit controlled by the receiver trigger device and the universal transmitting contact for controlling said correction or adjustment circuit. Pulses from 100 c.p.s. oscillator 1 are passed via limiter 2 and amplifier 3 to the first of four binary dividers 4, 5, 6 and 7 connected in cascade, the divider 7 providing a pulse output at 6.25 c.p.s. or a pulse spacing of 160 m. secs. The outputs from the dividers 5, 6, 7 are fed to a matrix 8 which is arranged to provide outputs to amplifiers 91 ... 98 at 20 m. secs. intervals, the output from 98 is fed over conductor 0101 to the divider 4 to shorten the cycle by 10 m. secs. to a figure of 150 m. secs. whilst the output from 97 is fed over connection 0103 to a gate circuit 10 which reduces the cycle time to 130 m. secs. when the circuit 10 is opened by a pulse on the conductor 0104 provided by a transmission-reception trigger 15. The blocking device 11 is unblocked and the oscillator 1 set into operation by the receiving trigger 12 on reception of a start element over input 29, or a pulse over contactor 0105 when transmission is from a keyboard 191; or from an answer-back transmitter 222. The oscillator 1 is stopped when the device 11 is blocked by a pulse over conductor 0101 from amplifier 9, or a pulse over conductor 0106 from an end-of-message detecting circuit 241. A test circuit 13 comprises elements 132 ... 136 which prevent sampling pulses passing to the primary storage devices 142 ... 146 when transmission is taking place, and also when a pulse is produced on conductor 67 by trigger 12 in response to the stop polarity at the input 29. The primary storage 14 comprises triggers 142 ... 14, storing the five code elements received or to be transmitted and a trigger 141 which indicates whether the signal stored is for transmission or reception. A resetting device 18 arranged to supply a restoring impulse during each cycle is operated by gate circuits 181, 183 controlled respectively by a pulse over conductor 0110 from amplifier 91 for transmission and from amplifier 98 over conductor 0109 for reception, the actual control being selected by a pulse from the trigger 141 through conductor 0105 and a pulse from the trigger 151 through conductor 0104. The secondary storage 15 comprises triggers 152 ... 156 to which the code elements on triggers 142... 146 are transferred, and a trigger 151 to which is transferred the cycle indication on trigger 141. The trigger 152 ... 156 control via amplifiers 162 ... 166 the magnets 172 ... 176 of the printer and also the coding device in a transmission cycle. A secondary resetting device 25 comprising a first element 251 controlled by amplifier 96 through conductor 0101 passes on a pulse over 0113 to reset triggers 152 ... 156 and a second element 252 controlled by amplifier 9, over conductor 0121 passes a pulse over conductor 0112 to reset the trigger 151. The amplifier 161 provides a pulse for the start magnet 171 of the printer and an amplifier 167 controls a magnet 177 positioning the two colour ink ribbon to distinguish the printing of received message and the " home "positioning messages transmitted to a distant receiver. A circuit 168 controlled from the resetting device 182 effects the resetting of the amplifiers 162 ... 166. The operation of the keyboard 191 effects the selective setting of the triggers 142 ... 146 and also the " transmit condition of the trigger 141 whilst the operation of a repetition may with a character key control a repetition device 192 to effect automatic repetition of the signal. A key controlling the transmission of the " answer back " signal passes a pulse over conductor 0115 to a code transmitter 222 which is stopped by a circuit 223. The signal transmitting assembly 20 comprises an output relay 201 amplifier 202 and a coding circuit 203 which is jointly controlled by the outputs of the matrix amplifiers 92 ... 98 over conductors 0116 and the outputs of the secondary storage triggers 152 ... 156 over conductors 0117 and the control over conductor 0104 by the trigger 151 which inhibits the operation of the circuit 20, if a received signal is stored. The received code signals are also passed over conductors 0117 to a circuit 21 which selects the figureshift signal and under control of a pulse over conductor 0104 passes a pulse over conductor 0120 to a circuit 221 which detects the letter D with the result that the circuit 221 initiates the operation of the " answer-back " 222 which passes the signals to the primary storage group 142... 146 and thence via the group 152 ... 156 to the output circuit. The answer back controls the trigger 141 to the transmit condition, renders the keyboard transmitter ineffective and passes pulses to a circuit 223 effecting the operation of the device 222 to set up the sequence of identification signals. A circuit 231 when primed by an output over the conductor 0120 from the circuit 21 detects the signal J and passes a pulse to a relay circuit 232 controlling a visible and/or an audible signal 27. A key 233 opens the alarm circuit and a device 234 detects the engaged signal passed over the lead 0107 from the trigger 12 and is associated with a blocking key 235 so that the signal is also operated when the apparatus is temporarily disabled. Contacts 236 closed when the paper is torn or its supply is exhausted operate the alarm circuit 232. A circuit 24 employed to detect the condition of the line comprises a counting device 241 which moves to position 1 in response to a signal corresponding to the busy condition and is moved under the control of the time-base to the final position in which it is indicative of the reception of the message and signal and through relay circuit 242 extinguishes the busy lamp 27 and stops the motor 26. It also passes a pulse over conductor 0106 to block the circuit 11 and stop the oscillator 1,whilst a pulse over conductor 0119 is effective to transmit the message-end signal via the coding device 203 to the output line 28. The various amplifiers and trigger circuits in most cases include transistors, are described in detail in connection with Figs. 2a to 2e (not shown). Specifications 733,071 and 802,987 are referred to.