US3264406A - Teleprinter control device - Google Patents

Teleprinter control device Download PDF

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Publication number
US3264406A
US3264406A US192461A US19246162A US3264406A US 3264406 A US3264406 A US 3264406A US 192461 A US192461 A US 192461A US 19246162 A US19246162 A US 19246162A US 3264406 A US3264406 A US 3264406A
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United States
Prior art keywords
line
transistor
telegraph
relay
state
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Expired - Lifetime
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US192461A
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English (en)
Inventor
Peter J Cohen
Francis R Firth
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Western Union Telegraph Co
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Western Union Telegraph Co
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Filing date
Publication date
Priority to BE631901D priority Critical patent/BE631901A/xx
Priority to NL292209D priority patent/NL292209A/xx
Application filed by Western Union Telegraph Co filed Critical Western Union Telegraph Co
Priority to US192461A priority patent/US3264406A/en
Priority to CH560063A priority patent/CH453422A/de
Priority to GB17777/63A priority patent/GB970606A/en
Application granted granted Critical
Publication of US3264406A publication Critical patent/US3264406A/en
Anticipated expiration legal-status Critical
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00—Data switching networks
    • H04L12/02—Details
    • H04L12/12—Arrangements for remote connection or disconnection of substations or of equipment thereof
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/50—Reducing energy consumption in communication networks in wire-line communication networks, e.g. low power modes or reduced link rate

Definitions

  • This invention relates to the printing telegraph, and more particularly to a novel unit for the remote control of a telegraph printer.
  • the receiving station it is necessary for the receiving station to recognize an incoming call, to turn on the locally-energized motor of the printer, to provide assurance that it is in receptive condition, and to provide a number of functions, later to be described, without assistance from an operator.
  • relays in general, comprise a source of considerable initial and maintenance expense, it is desirable to minimize their utilization in customer equipment provided that their function can be retained, or, as in the instant equipment, enlarged. Inherent limitations in size, weight, sensitivity, mounting position and environmental conditions, such as vibration, also can be circumvented thereby.
  • the instant invention is enabled to effectuate such advantage.
  • Still another object of the invention is to provide such a unit having the capacity to recognize polar switching signals without the use of a polar relay.
  • Another object of the invention is to provide such a unit adaptable to unitary integration into a compact dial, control and page-printer package.
  • the Central Ofiice provides a potential of 240 volts to the local loop telegraph pair connecting to this equipment, of a polarity arbitrarily termed positive. During such inactivity the equipment is required to present an impedance such that 5 milliamperes are drawn in the loop.
  • Such interruptions may be answered by a busy signal from the Central Ofiice, comprising a reversal to negative loop polarity for 200 milliseconds, followed by the restoration of positive idle polarity.
  • Termination of transmission from the local station as effected by momentary operation of a stop switch in the instant device, must cause continued interruption of loop current. This being answered by reversal to positive loop polarity by the Exchange, the device must then reduce the loop current to S-millia-rnperes idle current for maintenance of a guard circuit in the stand-by condition.
  • Receipt of a message by the local unit is essentially similar to the operation above described, the Exchange applying reversed polarity to the local loop in the same manner as upon making a successful connection to a called line during calling out from a local station, and the instant equipment, in consequence, being caused to start the printer motor for the receipt of message information.
  • FIG. 1 is a portion of a schematic wiring diagram of the instant invention.
  • FIG. 2 is the remainder of the schematic wiring diagram of FIG. 1.
  • the four relays employed in the invention have their relay coils designated A, H, W, and M, and their several contact pairs A1, H1 and H2, W1 and W2, and M1 respectively, which contact pairs are located on the drawings in proximity to their associated circuitry.
  • Such contacts are represented in the open position, which obtains when their respective coils are deenergized.
  • Transistors are shown to be energized through appropriate current limiting resistors and/ or blocking diodes from the symbols +18 or -18, the same referring to positive or negative voltages respectively supplied at the output of power supply 101, energized from mains current as shown, through fuses such as 102.
  • This pulse causes transistor Q1 to become non-conductive, this condition being assured by the application of reverse bias current limited by the resistor 16.
  • Transistor Q1 passes the pulse to its collector (energized through resistor 17) and through the resistors 18 and 19 to base of transistor Q2. Since transistors Q2 and Q3 are connected in well-known flip-flop configuration 34, this causes transistor Q3 to energize relay A and dial lamp D.
  • Resistors 103 and 104 connected between the collector of transistor Q3 and the base of Q2 comprise a crosscoupling resistor divided into two parts and having a capacitor 105 to the common ground connected therebetween.
  • the foregoing assembly comprises a means of slowing the switching speed of the transistor Q2 and Q3 in order to overcome the instability which would otherwise occur upon any introduction of an inductance such as that of the coil of relay A into the collector circuit of transistor Q3. Such instability would be caused by the presentation of an augmented impedance into the shunt path of such transients and thereby magnifying their amplitude in the cross-coupling circuit, if the instant circuitry were not employed.
  • a similar circuit comprising resistors 103', 104' and capacitor 105 operates in the circuit of transistors Q6 and Q5, later described, for similar protection of the coil of relay H.
  • Relay A thereby holds closed with its contacts Al the circuit'intiated by switch 14, any tendency toward excessive sparking of either being absorbed by the condenser 21 and resistor 22.
  • Dialing interruptions of the loop current take place at dial 20 and, upon their completion, loop polarity reversal to negative polarity is effected by the Exchange.
  • the reversal of polarity charges condenser 24 through delay resistor 25 and renders base of transistor Q5 positive.
  • rectifier 81 blocks the flow of current under this condition, enabling a charging voltage to build up. This reduces Q5 current through resistors 26 and 27 to place a positive potential on the base of transistor Q4, cutting it off.
  • Collector potential at transistor Q4 thus becomes negative and is applied through resistor 27 to the base of transistor Q6, lowering its resistance and energizing connect lamp C and relay coil H, whose contact H1 thereupon energizes printer 108 including the selector magnets such as 109 therein by an amplifier 119, through rectifier 23, conductive for this polarity, by connecting them across the telegraph loop.
  • transistor Q4 becomes non-conductive, and negative current is supplied from the collector thereof through resistor 29 to the base of transistor Q2, causing flip-flop Q2-Q3 to reverse and deenergize the proceed-to-dial lamp D and the relay A.
  • a diode 121 connecting the base of transistor Q5 to ground serves to limit to a safe value the reverse voltage applied to transistor Q5 and Q4 under connect conditions.
  • Switch contacts 107 in the dialing mechanism close during the dialing process, so that if dialing should occur during the connect period due to a mistake, a shunt path to maintain the operation of the selector magnets of printer 108 is provided.
  • Relay M is energized through resistor 31 and rectifier 32 by the conductivity of transistor Q6 under this condition, and its contact M1 connects motor 33 to the local power line.
  • relay H pulls in as before described but, since contacts W1 of relay W are in the energized position and the back contact therefore open, the energization of relay H connected thereto is therefore ineffective in this case to increase line current to the 60 milliamperes required to initiate reception.
  • Energization of relay H does, however, apply a positive potential to line 46, imposing it, after a time delay of about 2 seconds introduced by resistors 47 and 48 and capacitor 49, on the base of unijunction transistor Q7. This causes Q7 to break down through resistors 51, 52 and pass a positive charge shaped by capacitor 53 and resistor 54 through rectifier 55 to the line 56 for actuating fiipfiop 45 to release relay W.
  • Local switch 41 is thus rendered ineffective to alter this condition, even though closed during the period when connection or dialing persist.
  • any local request for a proceed-todial signal causes opening of a second set of contacts 143 thereon, removing the negative energization on the collector of transistor Q9 of flip-flop 45, whereby the base bias holding Q8 on (and thereby relay W energized) is removed, and relay W is deenergized to disengage local off-line operation.
  • start contacts 14B are connected to negative buss 42 only through stop contacts 35A, opening of the latter has the same effect of disengaging local operation as does depression of the start switch 14A.
  • Actuation of stop switch 35A acts in a similar manner to remove on bias from the collector of transistor Q3 in flip-fiop 34 to deenergize relay A and disengage the proceed-to-dial connection.
  • a low paper switch 71 is arranged to close when the record paper supply is near exhaustion. By thus connecting the base of transistor Q5 to positive buss 72 through resistors 73 and 74, and the rectifier 75, it prevents the application of any positive pulses to Q5 such as would cause it to initiate the energization of relay H (in the manner already described) to establish a connection for the transmission of outgoing messages or the receipt of incoming ones. Closure of switch 71 during operation of the printer on either incoming or outgoing messages, however, is ineffective to disrupt operation until after completion of the message because of the fact that transistor Q5 is functional only during switching of a connection, and passive at other times.
  • Switching for disconnection also is unaffected by switch 71 because the initiating polarity reversal then applied to the base of transistor Q5 is in such direction as not to be transmitted by the rectifier 75 to switch 71.
  • a telegraph system which comprises a central exchange, a telegraph line pair and a telegraph instrument adapted for line switching destination selection, control means for the instrument comprising:
  • resistor means and first diode means in circuit with said line for limiting current flow in one direction to a predetermined idle value
  • varistor means comprising a pair of oppositely conducting semiconductor diodes connected in parallel, and in circuit with said line for establishing a stabilized voltage drop thereacross upon line current flow therethrough;
  • first bistable transistor means having an on state and an off state, saturable transistor means connected thereto and to said varistor means for the switching of said first bistable transistor means to said on state only upon transistor desaturation induced by varistor means voltage drop extinction, back contacts on said momentary start switch means connected across the said saturable transistor means output to obviate saturable transistor means desaturation effect during start switch means inaction, said first relay being connected to said first bistable transistor means and responsive to the on state thereof to close its said contacts across said resistor means, for maintaining line calling current after transistor desaturation;
  • second diode means connected to said line and to the telegraph instrument and oppositely directed to said first diode means for flowing line current into the telegraph instrument upon line polarity reversal.
  • transistor means comprising a varistor in the line, for initiating a stable on state of electrical potential upon an interruption of line current in said one direction, including depressably closable start switch contact means across said resistor means as well as depressably openable start switch contact means in circuit with said transistor means for enabling initiation of said on state only during start switch depression;
  • relay means having contactsconnected across said resistor means and responsive to said stable on state of electrical potential to close said contacts
  • (2) means to establish a call current comprising callcurrent initiating means connected to the said linecurrent limiting means for deactivation thereof, and call-current maintaining means comprising callcurrent interruption detecting means in the line, bistable transistor means having an on state, connected and responsive thereto for establishing an on state upon detection of a call-current interruption, relay means connected and responsive to said bistable transistor means and connected to said linecurrent limiting means for deactivation thereof during an on state;
  • said call current initiating means having further means connected to said detecting means to provide detection only during limiting means deactivation;
  • telegraph instrument means on the line polarized for activation by active line polarity current.
  • (2) means to establish a call-current comprising callcurrent initiating means connected to the said line current limiting means for deactivation thereof and call-current maintaining means comprising call-current interruption detecting means in the line, first bistable transistor means having an on state, connected and responsive thereto for establishing an on state upon detection of a call-current interruption, first relay means connected and responsive to said bistable transistor means and connected to said limiting means for deactivation thereof during an on state;
  • said call current initiating means having further means connected to said detecting means to provide detection only during limiting means deactivation;
  • a telegraph system which comprises a central exchange, a telegraph line pair and a telegraph instrument adapted for line-switching destination selection, control means for the instrument comprising:
  • call means comprising current setting first relay means in the line having unilateral conductivity and first bistable transistor means including start switch means responsive to line-current interruption to set a calling current in the line;
  • (2) connect means comprising second relay means, transistor means connected to the telegraph line for energizing said second relay means in response to a change in line polarity, maintaining means therein for holding said second relay means energized after initial energization;
  • second bistable transistor means having an on state and an off state, and having third relay means therein responsive to said on state and connected to said telegraph instrument for energizing it thereby only during such on state therein;
  • avalanche transistor means connected to said second bistable transistor means for establishing an off state therein upon avalanche breakdown and having a connection to said connect means and responsive thereto to provide breakdown after connect means energization;
  • delay means associated with and active in conjunction with the last said connection to introduce a predetermined delay time before said breakdown after energization of said connect means
  • indicator means in circuit with contacts of said third relay means and of said second relay means energizable thereby to indicate the occurrence of any on state in said second bistable transistor means occurring during energization of said connect means.
  • a telegraph system which comprises a central exchange, a telegraph line pair and a telegraph instrument adapted for line switching destination selection, control means for the instrument comprising:
  • first bistable transistor means connected to the line and active to establish a calling current in one direction therein;
  • connect means comprising a transistor connected to the line and responsive to current in another direction therein to connect said telegraph instrument to the line;
  • second bistable transistor means connected to the line and responsive to the polarity thereof, having an on state and an oil? state, and having relay means therein responsive to said on state and connected to said telegraph instrument for energizing it thereby only during such on state therein;
  • avalanche transistor means connected to said second bistable transistor means for establishing an oil state therein upon avalanche breakdown, and having a connection to said connect means and responsive thereto to provide breakdown after connect meahs energization;
  • delay means associated with and active in conjunction with the last said connection to introduce a predetermined delay time before said breakdown after energization of said connect means.
  • a remote control unit for operating a printing telegraph instrument in conjunction with a telegraph line which includes first transistor means for establishing a calling current upon remote command when line current is in one direction, and second transistor means in the line enengizable for connecting the instrument to the line when line current is in the other direction, means for offline operation of the telegraph instrument which comprises:
  • bis-table transistor means having an on state and an o state, and having relay means therein responsive to said on state and connected to said telegraph instrument lfor energizing it thereby only during such on state therein;
  • avalanche transistor means connected to said bistable transistor means for establishing an off state there-in upon avalanche breakdown, and having a connection to said second tnansistor means and responsive thereto to provide breakdown after energization thereof;
  • delay means associated with and active in conjunction with the last said connection to introduce a predetermined delay time before said breakdown
  • indicator means in circuit with contacts of said relay means and connected to said second transistor means, energizable thereby to indicate the occurrence of any on state in said bistable transistor means occurring during energization of said second transistor means.
  • a telegraph system which comprises a central exchange, a telegraph tline pair and a motorized telegraph instrument adapted for line switching destination selection, control means for the instrument comprising:
  • ('1) first bistable transistor means connected to the line and active to establish a calling current in one direction therein;
  • connect means comprising a transistor connected to the line and responsive to current in another direction therein to connect said telegraph instrument to the line.
  • second bistable transistor means connected to the line and responsive to the polarity thereof, having an on state and an off state, and having first relay means therein responsive to said on state and connected to said telegraph instrument for energizing it thereby only during such on state therein;
  • avalanche transistor means connected to said second bistable transistor means lfOX establishing an off state therein upon avalanche breakdown, and having a connection to said connect means and responsive thereto to provide break-down after connect means energization;
  • motor-starting second relay means connected to said second bistable transistor means and responsive to an on state therein, and also connected to said connect means and responsive to an energized state thereof to start said motor in either case.
  • a telegraph system which comprises a central exchange, a telegraph line pair and a telegraph instrument adapted for line switching destination selection, control means tor the instrument comprising:
  • transistor means connected to the line for providing a connect circuit under another condition of line polarity, said means comprising relay means to initiate a connection of the instrument to the line upon receipt of a connect signal from the line;
  • switch means on the paper supply responsive to incipient paper exhaustion and connected to said means connected to the line for preventing only the initiation of instrument connection to the line.
  • a power supply for the transistors comprising power transformer means having a secondary winding with a center tap thereon, rectification means attached to said winding and in circuit with the transistors, said center tap being in conductive connection with the telegraph line during said calling period.
  • a remote control unit for a printing telegraph instrument which comprises bistable and line polarity sensitive transistorized calling means on a telegraph line, transistor actuated line polarity sensitive means to connect said instrument to a telegraph line, and bistable transistor means for effecting operation of the telegraph instrument out of connection with the telegraph line
  • positive and negative feeding power supply means for the transistors comprising varistor means across the telegraph line consisting of a pair of semiconductor diodes connected in parallel and oppositely poled, and a center tap in said power supply means having a polarity always substantially midway between said positive and negative feeds which is always in conductive connection with said varistor.
  • Means to provide augmented idle line current in a telegraph line for calling purposes which comprises a current limiting impedance in the line, varistor means to produce a relatively constant small voltage drop in the line which is effectively independent of line current, transistor means having an input connected across said varistor means, bistable transistor means having an on state and an off state in a current path and having an input connected to said transistor means for initiation of said on state by diminished conductance of said transistor means and relay means in said current path having contacts connected to said current limiting impedance whereby a discontinuity of line current causes discontinuance of the voltage drop across the varistor means to produce diminished conductance in transistor means for triggering the bistable transistor means to an on state for closing the relay contacts across the line impedance.
  • Means according to claim 7 for signalling the advent of telegraph messages on the line pair during off-line operation of the instrument which comprises means in said connect means operative for establishing a portion of a power circuit and means in said second bistable transistor means operative for establishing the remainder of said circuit, and signal means in said power circuit responsive to both aforesaid means to sound an alarm upon occurrence of the on state of said second bistable transistor means d-uring response of said connect means.
  • first bistable transistor means and said connect means and said second bistable transistor means each comprise a relay coil and a signal lamp having an incandescent filament ener-gizable therein, each said signal lamp being connected for operation in series With a said relay coil, whereby signal lamp life is extended.
  • a remote control unit for a printing telegraph instrument which comprises means to dial destination signals, means to connect a telegraph printer to the line, and means to provide off-line operation of the instrument,

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Communication Control (AREA)
  • Interface Circuits In Exchanges (AREA)
US192461A 1962-05-04 1962-05-04 Teleprinter control device Expired - Lifetime US3264406A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
BE631901D BE631901A (de) 1962-05-04
NL292209D NL292209A (de) 1962-05-04
US192461A US3264406A (en) 1962-05-04 1962-05-04 Teleprinter control device
CH560063A CH453422A (de) 1962-05-04 1963-05-03 Fernschreiber - Steuereinheit
GB17777/63A GB970606A (en) 1962-05-04 1963-05-06 Teleprinter control device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US192461A US3264406A (en) 1962-05-04 1962-05-04 Teleprinter control device

Publications (1)

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US3264406A true US3264406A (en) 1966-08-02

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US192461A Expired - Lifetime US3264406A (en) 1962-05-04 1962-05-04 Teleprinter control device

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US (1) US3264406A (de)
BE (1) BE631901A (de)
CH (1) CH453422A (de)
GB (1) GB970606A (de)
NL (1) NL292209A (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3453379A (en) * 1965-07-29 1969-07-01 Lawrence Holmes Jr Communication system
US3466404A (en) * 1964-11-18 1969-09-09 Siemens Ag Pulse transmission arrangement for telephone systems
US3673570A (en) * 1969-09-11 1972-06-27 Us Army Combination emitter follower digital line driver/sensor
US4054745A (en) * 1976-12-06 1977-10-18 Gte Automatic Electric (Canada) Limited Motor control device for data terminals

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US611638A (en) * 1898-10-04 Irjs peters co
US2351621A (en) * 1941-07-31 1944-06-20 Western Union Telegraph Co Printing telegraph exchange system
US2691889A (en) * 1949-04-26 1954-10-19 Bristol Company Plural zone measuring bridge
US2782254A (en) * 1953-10-13 1957-02-19 Automatic Elect Lab Tape measuring device for a teletypewriter message storing unit
US2843688A (en) * 1956-09-04 1958-07-15 Hughes Aircraft Co Tape controlled apparatus
US2993952A (en) * 1955-01-20 1961-07-25 American Telephone & Telegraph System for testing sequential code selector
US2993955A (en) * 1959-03-19 1961-07-25 James T Neiswinter Coded pulse train communication systems
US3005040A (en) * 1957-05-01 1961-10-17 Tesla Np Circuit closing and breaking arrangement for teleprinters
US3076056A (en) * 1958-11-17 1963-01-29 Automatic Elect Lab Telegraph signal arrangement for a telephone system

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US611638A (en) * 1898-10-04 Irjs peters co
US2351621A (en) * 1941-07-31 1944-06-20 Western Union Telegraph Co Printing telegraph exchange system
US2691889A (en) * 1949-04-26 1954-10-19 Bristol Company Plural zone measuring bridge
US2782254A (en) * 1953-10-13 1957-02-19 Automatic Elect Lab Tape measuring device for a teletypewriter message storing unit
US2993952A (en) * 1955-01-20 1961-07-25 American Telephone & Telegraph System for testing sequential code selector
US2843688A (en) * 1956-09-04 1958-07-15 Hughes Aircraft Co Tape controlled apparatus
US3005040A (en) * 1957-05-01 1961-10-17 Tesla Np Circuit closing and breaking arrangement for teleprinters
US3076056A (en) * 1958-11-17 1963-01-29 Automatic Elect Lab Telegraph signal arrangement for a telephone system
US2993955A (en) * 1959-03-19 1961-07-25 James T Neiswinter Coded pulse train communication systems

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3466404A (en) * 1964-11-18 1969-09-09 Siemens Ag Pulse transmission arrangement for telephone systems
US3453379A (en) * 1965-07-29 1969-07-01 Lawrence Holmes Jr Communication system
US3673570A (en) * 1969-09-11 1972-06-27 Us Army Combination emitter follower digital line driver/sensor
US4054745A (en) * 1976-12-06 1977-10-18 Gte Automatic Electric (Canada) Limited Motor control device for data terminals

Also Published As

Publication number Publication date
BE631901A (de)
CH453422A (de) 1968-06-14
GB970606A (en) 1964-09-23
NL292209A (de)

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