US2468065A - Telegraph system - Google Patents

Telegraph system Download PDF

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Publication number
US2468065A
US2468065A US660100A US66010046A US2468065A US 2468065 A US2468065 A US 2468065A US 660100 A US660100 A US 660100A US 66010046 A US66010046 A US 66010046A US 2468065 A US2468065 A US 2468065A
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US
United States
Prior art keywords
relay
code
armature
oscillating
relays
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US660100A
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English (en)
Inventor
Hartley George Clifford
Reynolds William John
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to BE482051D priority Critical patent/BE482051A/xx
Priority to GB3335/42A priority patent/GB555999A/en
Priority to US478735A priority patent/US2433362A/en
Priority claimed from US478735A external-priority patent/US2433362A/en
Priority to CH262919D priority patent/CH262919A/de
Priority to FR939075D priority patent/FR939075A/fr
Application filed by International Standard Electric Corp filed Critical International Standard Electric Corp
Priority to US660100A priority patent/US2468065A/en
Application granted granted Critical
Publication of US2468065A publication Critical patent/US2468065A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/20—Repeater circuits; Relay circuits
    • H04L25/202—Repeater circuits; Relay circuits using mechanical devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F25/00—Component parts of trickle coolers
    • F28F25/02—Component parts of trickle coolers for distributing, circulating, and accumulating liquid
    • F28F25/04—Distributing or accumulator troughs
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L17/00—Apparatus or local circuits for transmitting or receiving codes wherein each character is represented by the same number of equal-length code elements, e.g. Baudot code
    • H04L17/16—Apparatus or circuits at the receiving end
    • H04L17/30—Apparatus or circuits at the receiving end using electric or electronic translation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/20—Repeater circuits; Relay circuits
    • H04L25/205—Repeater circuits; Relay circuits using tuning forks or vibrating reeds

Definitions

  • the present invention relates to telegraph systems operating with a code such as the five-unit code, and is more particularly concerned with circuit arrangements for receiving such a code, which do not involve rotating mechanical systems.
  • the presentapplication is a division from our application Serial No. 478,735, filed March 10, 1943, now U. S. Patent 2,433,362 of Dec. 30, 1947.
  • a typical case of this kind is that in which an electric power supply system includes a means for periodically reporting the indications of watt meters or other like instruments located at a distance; the necessary information can in this case be conveyed by means of a few characters, and might be used to operate appropriate indicators, instead of being typed out.
  • Another example is the case where a circuit is used for the transmission of certain standardized orders to a distant point where they might be displayed on an indicator.
  • the present invention provides circuit arrangements chiefly employing ordinary commercial telephone type relays not requiring any special adjustments, and not involving any motor-driven mechanical systems. These circuits comprise a code receiver which can be used to store the characters and to use them to operate any suitable form of indicator or other receiving device.
  • a telegraph receiver for start-stop code signals comprising a pendulum relay, means for releasing the relay armature from a locked position to execute free oscillations, and means for returning the armature to a locked position after a predetermined number of swings.
  • Fig. 1 shows a schematic circuit diagram of a code receiver according to the invention.
  • Fig. 2 shows a diagramused to explalmthe operation of Fig. 1.
  • the signals to be received are start-stop five-unit code signals suitable for the conventional teleprinters operating at a speed of 50 words. It will be evident, however, that the same circuits are adaptable for other codes and speeds: it is quite possible, for example, that in some of the cases mentioned above to which the invention is specially suited, the information could be conveyed on a code with fewer units; in other circumstances more than five units might be preferable.
  • the weight should preferably be adjustable on the spring so that the vibration frequency can be varied.
  • the armature can be caused to execute free vibrations by cutting off the energising current, and so releasing it, and by a suitable circuit it may be given suitably timed impulses to maintain it indeflv tact" principle.
  • any connection to the battery or other constant potential source is indicated by an arrow-head pointing 3 away from a relay, and earth connections are indicated by the conventional symbol.
  • the positive terminal of the battery is supposed to be connected to earth, though the circuitwould operatethe other way Just as well.
  • spark quenching arrangements, current adjusting resistances and other like accessories not essential to the invention have been omitted, and may be supplied in any suitable manner known to those skilled in the art.
  • the marking condition of a line or circuit used for start-stop signals is the condition during which the circuit is temporarily idle, though ready to transmit characters, and the spacing condition is the opposite condition.
  • the actual state of the line or circuit that is, whether it is connected to positive or negative battery, or whether in the case of single current operation it is open or closed (and so on) during the marking condition will depend on the arrangements which have been chosen, and is' immaterial, so long as the chosen conditions are consistently maintained.
  • the signal element which is produced by the change to the marking condition will be called a marking element or mark, and the other element is the spacing element or space.
  • the start element is always a space
  • the stop element is always a "mark.”
  • the pendulum relay armature When the pendulum relay armature vibrates, it makes alternate swings from side to side and is always locked, and released from, the same side.
  • the word swing will be used to denote one movement of the armature; a complete vibration period therefore comprises two swings.
  • the incoming signals are applied at terminal 6 to the receiving relay RR, which is preferably a polar relay having marking and spacing contacts RRM and RRS.
  • the unit signals repeated by the relay RR are inspected by a. series of code storing relays VV, WW, XX, YY and Z2 each of which applies an earth to 2.
  • corresponding terminal I to 5 (which may be connected as desired to a receiving apparatus or storage system of any type), when the corresponding unit signal is a space.
  • a pendulum relay PB determines that the inspection shall be made during a short interval, say, about 5 milliseconds, in the middle of each millisecond unit interval, and a train of counting relays BB, CC, DD, EE and FF counts the swings of the pendulum relay and auses it to be locked up when the character has been received.
  • a second pendulum relay PA is used to delay the release of the first pendulum relay PB, so that the inspection periods occur in the middle of the 20 milliseconds signal intervals. The description below is based on a 5-millisecond cacao Idle, or ready to operate condition In the working condition of the circuit it is necessary for the two pendulum relays PA and PB to be locked up and for relay HH to be operated.
  • a slow-release relay HHR is provided.
  • HH and PA operate through contacts HHR-l and PB operates through its winding d and HER-2.
  • These contacts immediately break when HHR is operated by the closing of contacts HH-l, the relay HH locking itself and holding PA through its winding h and contacts HH--2 from. the earth obtained from contact RRM.
  • the relay HHR remains operated for the whole of the time the circuit is working, Its sole purpose is to reset the idle condition of the circuit when the batteries are first switched on.
  • PB is held through its winding h, and contacts PA-I, AR-i, and FF--l; contacts PA-2 being now open.
  • the receiving relay RR changes its armature over to the spacing side RR-S.
  • This operates relay AA which looks itself through its contacts AA5 and the contacts FF--2.
  • Relay AA prepares for subsequent operation relays AR (through AA
  • Timing relays PA and PB and of the other relays will be understood from the diagram of Fig. 2.
  • the various operations are there indicated with reference to a horizontal time scale divided at intervals of 20 milliseconds.
  • the start element is supposed to be received at zero time; the code elements arrive at 20, 40, 60, 80 and 100,
  • relay PB must execute free vibrations at as nearly as possible 25 complete cycles per second in order" to time the inspection correctly. It is found that relays oi the type described in the above mentioned specification and adjusted to 25 cycles take about 12 milliseconds to operate their contacts after being released from the locked position.
  • the inspection relays are high speed relays having an operate time of the order of 1 millisecond. To achieve the timing mentioned above the relay PA must introduce a delay of 14 /2 milliseconds and this will be attained if the relay is adjusted to a frequency of about 20 cycles per second. It will be understood that in practice the PA relay can be adjusted to give the exact time required for the case quoted above or to function with an inspection period of any other duration which may be convenient.
  • relay PA is released by the start signal at zero time. It opens the contacts PAI and releases PB at 14 milliseconds. PB swings over to the PBS side at about 27 /2 milliseconds. Meanwhile, Ofcourse, relay RR has changed back to the marking side for the first code element (assuming the character B to be received), but this has no immediate efiect. The changing over of the armature of relay PB has removed the earth from the inspecting relay HB and applied it to the other inspecting relay HA. These two relays should be very quick to operate, but should be given a releasing time of say, or 6 milliseconds by meansof the rectifier and condenser arrangement shown, for example.
  • relay E When relay E has operated, by closing its contacts Ell-2 it preparesrelays FF and KK to be energised by the pendulum relay on its swing at 107 milliseconds. These relays operate at about contacts HH-l and release about 12 milliseconds later (since they are unshunted).
  • the relay K by closing its contacts K--l to K-5 connects earth to the terminals I .to 5 according to the setting of the code storing relays W to ZZ. This earth is obtained through contacts AA-4, and relay KK provides an alternative earth through contacts KK6 because relay AA is released before the operation is complete.
  • relay K is finally released at about 144 milliseconds (t2 Fig. 2) it disconnects all the code storing relays which have been operated and these relays all release at about 158 milliseconds. All the operations which have been described are diagrammatically shown in Fig. 2)'.
  • relay FF provides the necessary locking circuit by closing its contacts FFI.
  • the release of AA has released AR by opening its contacts AA-i. This takes the locking ground oif relay PA (now held through winding 12.) and prepares the holding circuit for PB through ARI and PA-i.
  • relayFF is finally released after the operation of KK, .the earth is transferred from the winding (1 This is to ensure the release of EE.
  • the timing of the release of the inspecting relays HA and BB is carried out by shunting the windings with condensers CA and CB respectively having current limiting resistances of low value connected in series, and by providing the series rectifiers JAI and JA2.
  • the relay is energised through the rectifier and should operate very quickly as already explained, and the conseconds on the nextswing oi the relay PB. Relay It is possible for the second character denser is at the same time charged. when the circuit is broken by the pendulum relay PB, the condenser discharges through the relay holding it operated for the desired time, the other path being blocked by the rectifier.
  • Two other rectifiers'JA2 and J3 are provided to block the undesired alternative paths through the contacts of the counting relays by which the inspecting relays could be operated.
  • the earth for operating the code storing relays VV to ZZ is only applied for the 5 millisecond inspection period, and in order to ensure their proper operation, their windings are shunted by condensers CV to CZ in series withcurrent limiting resistances.
  • the condenser is charged up at the same time as the relay is energised, and when the circuit is broken at HA--l or HB-l, the condenser discharges through the winding of the relay and ensures its complete operation, and it then locks itself as already explained.
  • relay KK momentarily connects to earth any of the terminals l to 5 for which the corresponding code signal element is a space. It is assumed that these terminals will be connected to some storage or indicating device of any desired type.
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillation of said armature, means for operating said holding means after a predetermined number of oscillations of said armature to secure said armature again in said displaced position, means for receiving a succession of code unit elements at unit intervals corresponding to the oscillations of said relay, said receiving means including a polar relay, means for inspecting said code unit elements during a predetermined short period in each unit interval, said inspecting means including the first-mentioned relay which is adapted to be released on receipt of the start signal, a second oscillating relay adapted to be released by the first oscillating relay during its first'swing, and two similar fast operating inspecting relays adapted to be operated alternately during successive swings of said second oscillating relay.
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillationof said armature, means for operating said holding means after a predeterr'ined number of oscillations of said armature to secure said armature again in said displaced position, means for receiving a succession of code unit elements at unit intervals corresponding to the oscillations of said relay, said receiving means including a polar relay, means for inspecting said code unit elements during a predetermined short period in each unit interval, said inspecting means including the first-mentioned relay which is adapted to be released on receipt of the start signal, a second oscillating relay adapted to be released by the first oscillating relay during its first swing, and two similar fast operating inspecting relays adapted to be operated alternately during successive swings of said second oscillating relay, the frequency of oscillation of said second oscill
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillation of said armature, means for operating said holding means after a predetermined number of oscillations of said armature to secure said armature again in said displaced position, means forreceiving a succession of code unit elements at unit intervals corresponding to the oscillations of said relay, said receiving means including a polar relay, means for inspecting said code unit elements during a predetermined short period in each unit interval, said inspecting means including the first-mentioned relay which is adapted to be released on receipt of the start signal, a second oscillating relay adapted to be released by the first oscillating relay during its first swing, and two similar fast operating inspecting relays adapted to be operated altematelY during successive swings of said second oscillating relay, the vibration of said second oscillating relay
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillation of said armature, means for operating said holding means after a predetermined number of oscillations of said armature to secure said armature again in said displaced position, means for receiving a succession of code unit elements at unit intervals corresponding to the oscillations of said relay, said receiving means including a polar relay, means for inspecting said code unit elements during a predetermined short period in each unit interval, said inspecting means including the first-mentioned relay which is adapted to be released on receipt of the start signal, a second oscillating relay adapted to be released by the first oscillating relay during its first swing, and two similar fast operating inspecting relays adapted to be operated alternately during successive swings of said second oscillating relay, 9.
  • a telegraph code receiver for telegraph code signals comprislnga first oscillating relay having an armature capable of oscillating freely at a.
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillation of said armature, means for operating said holding means after apredeterminednumber of oscillations of said armature to secure said armature again in said displaced position, means for receiving a succession of code unit elements at unit intervals corresponding to the oscillations of said relay, said receiving means including a polar relay, means for inspecting said code unit elements during a predetermined short period in each unit interval, said inspecting means including the first-mentioned relay which is adapted to be released on receipt of the start signal, a
  • each inspecting relay being provided with a pair of make contacts connected in series with the operating circuit for the code storing relays, whereby the said operating circuit is closed only for the predetermined inspection period in each" code unit interval, and a plurality of counting relays associated with said code storing relays, each code storing relay bein adapted to be connected in turn to the operating circuit by a contact operated by the corresponding counting relay.
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillation of saidarmature, means for operating said holdin means after a predetermined number of oscillations of said armature to secure said armature again in said displaced position, means for receiving a succession of code unit elements at unit intervals corresponding to the oscillations of said relay, said receiving means including a polar relay, means for inspecting said code unit elements during a predetermined short period in each unit interval, said inspecting means including the first-mentioned relay which is adapted to be released on receipt of the start signal, a second oscillating relay adapted to be released by the first oscillating relay during its first swing, and two similar'fast operating inspecting relays adapted to be operated alternately during suc-' cessive swings of said second oscillating relay, a separate conden
  • a telegraph code receiver for telegraph code signals comprising. a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillation of said armature, means for operating said holding means after a predetermined number of oscillations of said armature to secure said armature again in said displaced position, means for receiving a.
  • said receiving means including a polar relay, means for inspecting said code unit elements during a predetermined short period in each unit interval, said inspecting means including the first mentioned relay which is adapted to be released on receipt of the start signal, a second oscillating relay adapted to be released by the first oscillating-relay during its first swing, and two similar fast operating inspecting relays adapted to be operated alternately during successive swings of said second oscillating relay, and means for locking the armature of said first oscillating relay immediately after its second swing.
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position,
  • a telegraph code receiver for telegraph code signals comprising a first oscillating relay having an armature capable of oscillating freely at a predetermined rate, means for holding said armature displaced from its normal position, means for releasing said holding means to permit free oscillation of said armature, means for operating said holding means after a predetermined number of oscillations of said armature to 12 secure said armature again in said displaced position, means for receiving a succession of code unit elements at unit intervals, corresponding to the oscillations of said relay, said receiving means including a polar relay, means for inspecting said code' unit elements during a predetermined short period in-each unit interval, said inspecting means including the first-mentioned relay which is adapted to be released on receipt of the start signal, a second oscillating relay adapted to be released by the first oscillating relay during its first swing, and two similar fast operating inspecting relays adapted to be operated alternately during successive swings of said second oscillating relay, said receiver being adapted to receive a five

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Relay Circuits (AREA)
US660100A 1942-03-13 1946-04-06 Telegraph system Expired - Lifetime US2468065A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
BE482051D BE482051A (hu) 1942-03-13
GB3335/42A GB555999A (en) 1942-03-13 1942-03-13 Improvements in or relating to electric code signalling systems
US478735A US2433362A (en) 1942-03-13 1943-03-10 Pendulum relay controlled startstop telegraph transmitter
CH262919D CH262919A (de) 1942-03-13 1946-01-07 Elektrische Signalisieranlage.
FR939075D FR939075A (fr) 1942-03-13 1946-04-01 Perfectionnements aux systèmes et aux appareils télégraphiques
US660100A US2468065A (en) 1942-03-13 1946-04-06 Telegraph system

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB262919X 1942-03-13
US478735A US2433362A (en) 1942-03-13 1943-03-10 Pendulum relay controlled startstop telegraph transmitter
US660100A US2468065A (en) 1942-03-13 1946-04-06 Telegraph system

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US2468065A true US2468065A (en) 1949-04-26

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Application Number Title Priority Date Filing Date
US660100A Expired - Lifetime US2468065A (en) 1942-03-13 1946-04-06 Telegraph system

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US (1) US2468065A (hu)
BE (1) BE482051A (hu)
CH (1) CH262919A (hu)
FR (1) FR939075A (hu)
GB (1) GB555999A (hu)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2546369A (en) * 1942-10-06 1951-03-27 Roelof M M Oberman Start-stop repeater
US2606243A (en) * 1947-08-04 1952-08-05 Cie Ind Des Telephones System for reception of coded signals
US2786938A (en) * 1951-01-23 1957-03-26 Gen Railway Signal Co Code communication system
US2850718A (en) * 1954-02-04 1958-09-02 Automatic Telephone & Elect Counting circuits
US2884617A (en) * 1953-09-21 1959-04-28 Charles F Pulvari Methods and apparatus for recording and reproducing intelligence
US2888665A (en) * 1954-11-08 1959-05-26 Hardt Foundation Electrically operated selector
US3360776A (en) * 1963-04-12 1967-12-26 Gen Signal Corp Code communication system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1967396A (en) * 1927-12-02 1934-07-24 Louis L E Chauveau Alarm selector apparatus
US2210577A (en) * 1938-09-16 1940-08-06 Ibm Signaling system
US2400574A (en) * 1943-12-11 1946-05-21 Bell Telephone Labor Inc Start-stop receiving selector mechanism

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1967396A (en) * 1927-12-02 1934-07-24 Louis L E Chauveau Alarm selector apparatus
US2210577A (en) * 1938-09-16 1940-08-06 Ibm Signaling system
US2400574A (en) * 1943-12-11 1946-05-21 Bell Telephone Labor Inc Start-stop receiving selector mechanism

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2546369A (en) * 1942-10-06 1951-03-27 Roelof M M Oberman Start-stop repeater
US2606243A (en) * 1947-08-04 1952-08-05 Cie Ind Des Telephones System for reception of coded signals
US2786938A (en) * 1951-01-23 1957-03-26 Gen Railway Signal Co Code communication system
US2884617A (en) * 1953-09-21 1959-04-28 Charles F Pulvari Methods and apparatus for recording and reproducing intelligence
US2850718A (en) * 1954-02-04 1958-09-02 Automatic Telephone & Elect Counting circuits
US2888665A (en) * 1954-11-08 1959-05-26 Hardt Foundation Electrically operated selector
US3360776A (en) * 1963-04-12 1967-12-26 Gen Signal Corp Code communication system

Also Published As

Publication number Publication date
GB555999A (en) 1943-09-15
FR939075A (fr) 1948-11-03
BE482051A (hu)
CH262919A (de) 1949-07-31

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