US1379243A - Telegraph system - Google Patents

Telegraph system Download PDF

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Publication number
US1379243A
US1379243A US210148A US21014818A US1379243A US 1379243 A US1379243 A US 1379243A US 210148 A US210148 A US 210148A US 21014818 A US21014818 A US 21014818A US 1379243 A US1379243 A US 1379243A
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relays
relay
contacts
line
current
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US210148A
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John H Bell
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AT&T Corp
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Western Electric Co Inc
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Priority to US210148A priority Critical patent/US1379243A/en
Priority claimed from US249812A external-priority patent/US1336414A/en
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/38Synchronous or start-stop systems, e.g. for Baudot code
    • H04L25/40Transmitting circuits; Receiving circuits
    • H04L25/49Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems

Definitions

  • This invention relates to telegraphic systems and more particularly to systems of submarine telegraphy.
  • the principal object of this invention is to provide an improved organization of apparatus for overcoming the phenomenon known as wandering zero experienced in line conductors having high electrostatic capacity.
  • the present invention contemplates the use of a plurality of electroresponsive devices to cooperate with a transmitting system in establishing operations whereby a cable or line conductor will be connected to the earth during such impulse intervals as would otherwise require that a recurrence or a successive repetition of current impulses of like polarity should take place.
  • Figure 1 is shown a transmitting system suitable for practising the features of this invention
  • Fig. 2 is shown in a theoretical form the relation of current impulses which form permutations of polarities suitable for the transmission of signals. 7
  • the transmission arrangement has for convenience been based on the use of the well known five-unit'code selecting system of Baudot, and before entering upon a more detailed description of the system a brief allusion will be made to the general control of the contacts A establish changes of current polarity by way of contactscontrolled by a group of relays with the segments of a multiplex distributer D at which a line or cable conductor 99 is terminated.
  • the relays C serve to substitute an earth connection for intervals corresponding with successive repetition of impulses of like polarity which may have been selected by the relays B, for energlzlng segments of the dis tributer D, through which predeterminedly. prepared comblnationsof current or earth connectionsbecome effective with the line 99.
  • a dividingline 69 separates a transmitter equipment suitable for operating a single channel of the multiplex equipment which lies at the left-hand side of this line, from a transmitting equipment for a second channel of the multiplex which is shown at the right-hand side of the line 69.
  • the distributer D ha been shown in developed form, ,it will be understood that it should preferably be of a rotary type, and if the distributor is of quadruplex capacity the equipment shown at the left-hand side of the line 69 would correspond with one quadrant or arm, while the equipment shown at the right-hand side of the dividing line would correspond with mon or bus conductor 59 with the left-hand or normal contact stop of each one of the transmitter contacts of the first channel and with the right-hand or forward stop of each transmitter contact of the second channel,
  • each relay of the group B is under the control of a corresponding one of the transmitter contacts A.
  • a bus, conductor connected from one winding terminal of each of the five relays B of the first channel extends to the negative bus conductor 59, while a bus conductor extends fromone winding terminal of each of the five relays B of the second channel to the positive bus conductor 49. Therefore, so long as a transmitter lever in either channel is on its normal contact stop no current will flow through the associated one of the relays B. l/Vhen a transmitter lever is moved from its normal to its oppositely energized contact stop, however, a circuit will be established for the associated relay B through which current from the battery 50 will act accumulatively with current from the battery 60, thereby operating the relay.
  • the control circuits of the compoundwoundrelaysC may be seen to be arranged in such a manner that each relay is connected to the respectively adjacent left-hand and right-hand positioned ones of the transmitter levers A.
  • the connective relation of the two windingson each of these relays is such that when currents of like polarity are applied to the non-grounded terminal of each winding the relay will be operated. It will therefore be clear that so long as two adjacent transmitter levers are both on either their negative or their positive contact stops the associated relay 0 will be operated, and conversely, during such time as the two adjacent transmitter levers may be positioned, one on its negative stop, while the other lever is on its positive contact stop, the associated one of the relays C which falls intermediate these transmitter levers will be deenergized.
  • the transmitter contacts A will be positioned to prepare permutations of current impulses which will correspond with the ten impulse intervals shown in Fig. 2 of the drawing.
  • the transmitter levers at 1, 31, 41, 61 and 91 will remain on their normal contact stops, while the levers at 11, 21, 51, 71 and 81 will be moved to engage their respective forward contact stops.
  • the result of these circuit changes is the operation of the relays 12, 22, 52, 72 and 82 of the group B, and the releasing of the relays 15, 35, 65, 75 and 95 of the group C.
  • the relays 2, 32, 42, 62 and 92 of the group B continue inert, while the relays 25, 45, 55 and of the group C continue operated.
  • the relay 5 continues in its normal inert position. To specifically point out the differential circuits whereby the six relays 01 the group G are deenergized during the present combination, negative current from the transmitter contacts 1 through the right-hand winding of the relay 5 to earth is opposed by positive current from the transmitter contacts 91 established over a conductor 79 through the left-hand winding of the relay 5 to earth, thereby releasing this relay.
  • a circuit may accordingly be traced from a negatively poled and grounded line battery 20 by way of a bus conductor 19, the contacts 3 of the relay 2, the contacts 6 of the relay 5 to the segment 8, from which point the circuit continues through the brush 40 to a ring section 39 and thence to the line conductor 99. For the next impulse a circuit may be traced from.
  • a positively poled and grounded line battery 30 by way of a bus conductor 29, the contacts 7 14 of the relay 12, the contacts 16 of the relay 15 to the segment 18, and on the brush of the relay 32, and the contacts 36 of the rebus:89 through the contactsLT of the relay l5, and the segment 58 is connected through the contacts 57 of the relay 55- with the ground bus 89'; therefore in passing over these segmentsthe brush L0 causes the cable 99 to be grounded; Current from the positively poled bus 29 completes-circuit over the contacts 63of the relay 62, thccontacts 66 of the relay'6'5, and at a proper'moment' from the segment 68by way of-the brush 4:0 to the line 99.
  • lVhen over the segment 88the brush 40 causes the line to be grounded through the contacts 87 of the relay 85, and on finally arriving over the.
  • last segment 98'the-brush 410 connects the line throughthe-contacts 96 of the relay and the contacts 93 of the relay 92 withthe positive current bus '29.
  • the blank intervals in this line correspond with the intervals during which the cable or line 99 was grounded in substitution of the prepared impulses of current as indicated at the corresponding impulse spaces in the upper current line.
  • the successive changes taking place with the line 99 were in the order of a negative impulse, a positive impulse, ground interval, a negative impulse and a ground interval.
  • the transmission progressed in the order of a ground interval, a positive impulse, a negative impulse, a ground interval and a positive impulse.
  • receiving equipment at the distant end of the cable 99 will be present to suitably translate the impulses and changes of electrical condition of the line into respective message records.
  • a line circuit a plurality of transmitting contacts, a plurality of relays controlled by said contacts, a distributer, means jointly controlled by said plurality of contacts, said relays and said distributer for establishing changes of current polarity with said line, and a second plurality of relays controlled by said transmitting contacts to render the distributer effective to ground said line in substitution of an immediately succeeding repetition in said line circuit of an impulse of one polarity.
  • a line conductor sources of current having opposite polarities, transmitting contacts, a distributer, relays controlled by said contacts for establishing ermutations of current polarities with said distributer, means operated by said distributer for establishing said permutations of polarities with said line circuit, a plurality of compound wound relays, means controlled by successively adjacent ones of said transmitter contacts for controlling the operation of respectively associated ones of said last mentioned relays, and means controlled by said compound wound relays to said transmitting means for establishing. permutations of current impulseswith said.
  • a telegraphsystem comprising a line
  • a plurality of sources of current of opposite polarity a tape transmittena plurality of and a second group of relays controlled by.
  • relays energized in accordance with the actuation of said transmitter, a distributer for applying; to said line currentimpulses as established by the operation of said relays,
  • said transmitter for. elfectively grounding said line in substitution of successive repetition of current impulses of thesame polarity. j -V I i 5.
  • a pole -changerrelay for each of saidsegments, acselecting switch.
  • a pole changer relay for each of said segments, a selecting switch individual to each, of said relays and having the contacts thereof arranged to normallyrender said relays inert, and. a set of differential relays operated in accordance with the actuation of two adjacent-selecting switches for disconnecting a corresponding segment of said distributerfromits associate pole changerandto connect it to ground.

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  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Description

J. H. BELL.
TELEGRAPH SYSTEM.
APPLICATION FILED JANA 3, 1918. 1,379,243.
Patente Ma 24,1921.
UNITED sTAr s PATENT OFFICE.
JOHN H. BELL, OF SOUTH ORANGE, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC" COMPANY, INCORPORATED, OF NEW] YORK, N. Y., A CORPORATION OF YORK.
TELEGRAPH SYSTEM.
Specification of Letters Patent.
Patented May 24, 1921.
Application filed January 3, 1918. Serial No. 210,148.
To all whom it may concern:
Be it known that I, Jenn l'l. BELL, a citizen of the UnitedStates, residing at South Orange, in the county of Essex, State of New Jersey, have invented certain new and useful Improvements in Telegraph Systems, of which the following is a full, clear, concise, and exact description.
This invention relates to telegraphic systems and more particularly to systems of submarine telegraphy. I
The principal object of this invention is to provide an improved organization of apparatus for overcoming the phenomenon known as wandering zero experienced in line conductors having high electrostatic capacity.
It is well known that due to the high condenser eiiect and the resulting low time constant of submarine telegraph. conductors, a
reponderancc of current of one polarity will have the effect of counteracting or dominating a current of inverse polarity to the extent that a so-calledchoking of the conductor is likely to delay or otherwise interfere with signaling impulses. It is therefore considered desirable in signaling over lines of this character to employ, if possible, means for establishing true reversals of current polarity in order that uniformity in the charging and discharging of the cable may be had.
To the above end the present invention contemplates the use of a plurality of electroresponsive devices to cooperate with a transmitting system in establishing operations whereby a cable or line conductor will be connected to the earth during such impulse intervals as would otherwise require that a recurrence or a successive repetition of current impulses of like polarity should take place.
This system is illustrated diagrammatically in the accompanying drawing, in which only so much of a telegraphic transmitting system is shown as will be necessary to a clear understanding of the invention.
In the drawing, Figure 1, is shown a transmitting system suitable for practising the features of this invention, and in Fig. 2 is shown in a theoretical form the relation of current impulses which form permutations of polarities suitable for the transmission of signals. 7
' In the embodiment" chosen for illustrating this invention, the transmission arrangement has for convenience been based on the use of the well known five-unit'code selecting system of Baudot, and before entering upon a more detailed description of the system a brief allusion will be made to the general control of the contacts A establish changes of current polarity by way of contactscontrolled by a group of relays with the segments of a multiplex distributer D at which a line or cable conductor 99 is terminated. The relays C serve to substitute an earth connection for intervals corresponding with successive repetition of impulses of like polarity which may have been selected by the relays B, for energlzlng segments of the dis tributer D, through which predeterminedly. prepared comblnationsof current or earth connectionsbecome effective with the line 99.
In more specifically describing this system, it will first be pointed out that for convenience of description a dividingline 69 separates a transmitter equipment suitable for operating a single channel of the multiplex equipment which lies at the left-hand side of this line, from a transmitting equipment for a second channel of the multiplex which is shown at the right-hand side of the line 69. Although the distributer D ha been shown in developed form, ,it will be understood that it should preferably be of a rotary type, and if the distributor is of quadruplex capacity the equipment shown at the left-hand side of the line 69 would correspond with one quadrant or arm, while the equipment shown at the right-hand side of the dividing line would correspond with mon or bus conductor 59 with the left-hand or normal contact stop of each one of the transmitter contacts of the first channel and with the right-hand or forward stop of each transmitter contact of the second channel,
while a positively poled source ofgrounded current 50 is connected by way of a bus conductor 49 with each one of the forward or right-hand contact stops of the transmitter contacts in the first channel and with the left-hand or normal contact stop of each transmitter contact in the second channel. It will also be noted that each relay of the group B is under the control of a corresponding one of the transmitter contacts A. A bus, conductor connected from one winding terminal of each of the five relays B of the first channel extends to the negative bus conductor 59, while a bus conductor extends fromone winding terminal of each of the five relays B of the second channel to the positive bus conductor 49. Therefore, so long as a transmitter lever in either channel is on its normal contact stop no current will flow through the associated one of the relays B. l/Vhen a transmitter lever is moved from its normal to its oppositely energized contact stop, however, a circuit will be established for the associated relay B through which current from the battery 50 will act accumulatively with current from the battery 60, thereby operating the relay.
The control circuits of the compoundwoundrelaysC may be seen to be arranged in such a manner that each relay is connected to the respectively adjacent left-hand and right-hand positioned ones of the transmitter levers A. The connective relation of the two windingson each of these relays is such that when currents of like polarity are applied to the non-grounded terminal of each winding the relay will be operated. It will therefore be clear that so long as two adjacent transmitter levers are both on either their negative or their positive contact stops the associated relay 0 will be operated, and conversely, during such time as the two adjacent transmitter levers may be positioned, one on its negative stop, while the other lever is on its positive contact stop, the associated one of the relays C which falls intermediate these transmitter levers will be deenergized. It therefore follows that during the time all of the transmitter levers A are in their normal positions, all of the relays C, except the two relays 5 and 55, will be operated by current either from the source 50 or the source 60 which complete circuit through the transmitter contacts and both windings of each relay to the earth connections. In order that the position of the equipment will be consistent with the circuits normally established, the relays C are shown in their respectively normal positions as energized or non-energized.
For convenience in further describing this system, let it now be assumed that in response to one control tape for the first channel and another control tape for the second channel, the transmitter contacts A will be positioned to prepare permutations of current impulses which will correspond with the ten impulse intervals shown in Fig. 2 of the drawing. For this combination the transmitter levers at 1, 31, 41, 61 and 91 will remain on their normal contact stops, while the levers at 11, 21, 51, 71 and 81 will be moved to engage their respective forward contact stops. The result of these circuit changes is the operation of the relays 12, 22, 52, 72 and 82 of the group B, and the releasing of the relays 15, 35, 65, 75 and 95 of the group C. The relays 2, 32, 42, 62 and 92 of the group B continue inert, while the relays 25, 45, 55 and of the group C continue operated. The relay 5 continues in its normal inert position. To specifically point out the differential circuits whereby the six relays 01 the group G are deenergized during the present combination, negative current from the transmitter contacts 1 through the right-hand winding of the relay 5 to earth is opposed by positive current from the transmitter contacts 91 established over a conductor 79 through the left-hand winding of the relay 5 to earth, thereby releasing this relay. In a similar manner, oppositely poled currents from the transmitter contacts ,1 and 11 deenergize the relay 15, the contacts 21 and 31 effect releasing of the relay 35, contacts 51 and 61 cause relay 65 to release, contacts 61 and 71 cause the relay 7 5 to release and the contacts 81 and 91 cause the relay 95 to be released. It may be mentioned that negative current from each of the transmitter contacts 41 and 51 causes the relay 55, normally inert, to be operated.
Since automatic transmitting mechanism (not shown) retains the circuits just traced until a trailer or, contactor brush 40 has traversed its path from left to right on the distributor D, let it now be assumed that this brush has arrived over the first segment 8. A circuit may accordingly be traced from a negatively poled and grounded line battery 20 by way of a bus conductor 19, the contacts 3 of the relay 2, the contacts 6 of the relay 5 to the segment 8, from which point the circuit continues through the brush 40 to a ring section 39 and thence to the line conductor 99. For the next impulse a circuit may be traced from. a positively poled and grounded line battery 30 by way of a bus conductor 29, the contacts 7 14 of the relay 12, the contacts 16 of the relay 15 to the segment 18, and on the brush of the relay 32, and the contacts 36 of the rebus:89 through the contactsLT of the relay l5, and the segment 58 is connected through the contacts 57 of the relay 55- with the ground bus 89'; therefore in passing over these segmentsthe brush L0 causes the cable 99 to be grounded; Current from the positively poled bus 29 completes-circuit over the contacts 63of the relay 62, thccontacts 66 of the relay'6'5, and at a proper'moment' from the segment 68by way of-the brush 4:0 to the line 99. At the segment 78 the brush connects the line 99=through the con'- tacts 76 of the relay and the" contacts 74 of the'relay 72 with the negative bus 19. lVhen over the segment 88the brush 40 causes the line to be grounded through the contacts 87 of the relay 85, and on finally arriving over the. last segment 98'the-brush 410 connects the line throughthe-contacts 96 of the relay and the contacts 93 of the relay 92 withthe positive current bus '29.
From the foregoing'description it will 'beclear that a succession of impulses prepared" by the transmitted'equipment in accordance with the uppermost current line in Fig. 2'
would require five successive impulses in the order of a negative,- positive,positive, nevative and negative impulse for the first telegraphic channel, while five successive impulses in the order of a negative, positive, negative, negative and positive impulse would be required for the second channel of the multiplexed line. Referring to the lowermost current line in Fig. 2, the blank intervals in this line correspond with the intervals during which the cable or line 99 was grounded in substitution of the prepared impulses of current as indicated at the corresponding impulse spaces in the upper current line. For the first channel the successive changes taking place with the line 99 were in the order of a negative impulse, a positive impulse, ground interval, a negative impulse and a ground interval. For the second channel the transmission progressed in the order of a ground interval, a positive impulse, a negative impulse, a ground interval and a positive impulse.
It will be understood that receiving equipment at the distant end of the cable 99 will be present to suitably translate the impulses and changes of electrical condition of the line into respective message records.
For convenience in the foregoing description it was assumed that the control tape of the first and second channel respectively prepared their combination of impulses at the same time; it will be understood however that this would not necessarily be the case as it would only require that the circuits of the second channel be prepared in advance of the arrival of the brush 40 over the last segment 48 in the distributer sectlOIl. of the first channel. It will also be further understood that. the tape" control mechanism (not shown, but well understood in the=art) would not'act to clear outa set up of the circuits of thefirstchannel until the brush 40 had passed from the first seg ment 58 of the second channel. This relationoffthe channels would, of: course, apply between each channel orquadrant of a quadruplex distributer or the sextants of a sextuplex distributer, etc. Itwill, of course, be obviousthat instead of two or more channels, the distributer may be arranged to operate only asingle channel, in which case the brush 40, after: leaving a last segment as the segment 48-, would enter upon a first segment or a segment interc0nnected=tocorrespondwith the segment 8. Since-the form and circuit arrangement of eachof the relays in-the; group B are typical one relay with another, and as this is also true of the relays inthegroup G, one'with another, uniform progressions of reference numerals have been employed in designatmg llke partsof' the various equipments which correspond with the .several segments or impulse intervals of the distributor. It will, accordingly, be convenient to trace anyone ofthe'various'permutations or comb1nat1ons of impulses which this system is capable of, vpreparing and. transmitting,
therefore further description of the system will not be necessary.
What is claimed is:
1. In a system of telegraphy in which signaling is effected through permutations of impulses having different polarities, a line circuit, a plurality of transmitting contacts, a plurality of relays controlled by said contacts, a distributer, means jointly controlled by said plurality of contacts, said relays and said distributer for establishing changes of current polarity with said line, and a second plurality of relays controlled by said transmitting contacts to render the distributer effective to ground said line in substitution of an immediately succeeding repetition in said line circuit of an impulse of one polarity.
2. In a telegraph system, a line conductor, sources of current having opposite polarities, transmitting contacts, a distributer, relays controlled by said contacts for establishing ermutations of current polarities with said distributer, means operated by said distributer for establishing said permutations of polarities with said line circuit, a plurality of compound wound relays, means controlled by successively adjacent ones of said transmitter contacts for controlling the operation of respectively associated ones of said last mentioned relays, and means controlled by said compound wound relays to said transmitting means for establishing. permutations of current impulseswith said.
line, and means rendered effective upon the operation of said means by SIICOESSIVGCUT- rentv impulses of the same polarity. for
grounding said line insubstitution of -suc-- cessive repetition of current impulses of the same polarity. V
*4. A telegraphsystem comprising a line,
a plurality of sources of current of opposite polarity, a tape transmittena plurality of and a second group of relays controlled by.
relays energized in accordance with the actuation of said transmitter, a distributer for applying; to said line currentimpulses as established by the operation of said relays,
said transmitter for. elfectively grounding said line in substitution of successive repetition of current impulses of thesame polarity. j -V I i 5. In a telegraph system, in combination with a distributer having a plurality of transmitting segments, a pole -changerrelay for each of saidsegments, acselecting switch.
individual to eachjof said relays forcontrolling the operation thereof, and a set of differential relays, each of which is under the joint control of two adjacent selecting segments, a selecting switch individualto each of said relays and having the contacts thereofarranged to normally render'said relays inert, and a setof diflr'erential relays operated in accordance with the actuation of said selecting switches for controlling the connection of the associate pole changer with a corresponding segment of said distributer.
7. Ina telegraph system, in combination with a distributer having a plurality of segments, a pole changer relay for each of said segments, a selecting switch individual to each, of said relays and having the contacts thereof arranged to normallyrender said relays inert, and. a set of differential relays operated in accordance with the actuation of two adjacent-selecting switches for disconnecting a corresponding segment of said distributerfromits associate pole changerandto connect it to ground. 7
Inwitness whereof, I hereunto subscribe my name this 27th day of December, A. 11,1917 ,o
pole changer andto connect v JOHN BELL;
US210148A 1918-01-03 1918-01-03 Telegraph system Expired - Lifetime US1379243A (en)

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US249812A US1336414A (en) 1918-08-14 1918-08-14 Telegraphy

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