US1730614A - Synchronous vibratory relay system - Google Patents

Synchronous vibratory relay system Download PDF

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US1730614A
US1730614A US228706A US22870627A US1730614A US 1730614 A US1730614 A US 1730614A US 228706 A US228706 A US 228706A US 22870627 A US22870627 A US 22870627A US 1730614 A US1730614 A US 1730614A
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relay
vibrating
tongue
winding
contact
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US228706A
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William A Knoop
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AT&T Corp
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Bell Telephone Laboratories Inc
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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
    • H04L25/44Transmitting circuits; Receiving circuits using relay distributors

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  • This invention relates to high speed synchronous telegraph systems in which short signal impulses are excessively attenuated and must be rebuilt, or regenerated, at the receiving station, and its object is to simpliy and increase the reliability of thepequipment at the receiving station for rebuilding short signal impulses.
  • the present system eliminates the necessity of using, in a vib'ratory relay system, more than two polar relays and more than one lain and one segmented ring on the receiv- Furthermore, in rthis system the necessity of connecting opposite contacts of a relay to sources of current of opposite polarity has been eliminated; therefore rotective resistances are not required in the attery leads, and as a result no separate printing relay is required.
  • Fig. 1 represents a complete system for the regeneration and printing of signal impulses -received over a telegraph conductor
  • Fig. 2 contains curves illustrating the operation of the apparatus in Fig. l;
  • Fig. 3 illustrates an alternative arrangement for repeating impulses to another line.
  • the vibrating relay circuit proper comprises a main vvibrating relay MVR and auxiliary vibrating relay AVR, vibrating rings VR, on a receiving distributor, and the circuit shown in heavy lines.
  • Both MVR and AVR are high speed polar relays with two independent windings on each so disposed that an electron flow from left to right moves the associated relay tongue to the right and an electron flow from right to left moves the associated tongue to the left.
  • rl ⁇ he two windings on the main vibrating relay MVR function independently of each other, the upper winding LW being the line winding, which may be connected to the telegraph conductor L1 through an amplifier as shown, and the lower winding VW forming a part of the vibrating circuit.
  • the operating current for the lower winding VW is limited by resistance 7 or resistance 8 to such a low value that the operation of the relay is controlled by the line winding LW, whenever a signal impulse of any substantial magnitude is received over the line conductor L1.
  • Resistances 3 and 4 are ⁇ for contact protection only and do not need to be considered in following the operation of the system. Likewise resistances 14 and l5 shunted across the windingspf relay AVR are to improve the operating characteristics of that relay and may be disregarded. l
  • Curve 27 represents the form of the wave transmitted from a distant station on conductor L1
  • curve 28 represents the form of the received current after it is amplilied and applied to the line winding LW of the main vibrating relay. Curves 27 and 28 would actually be displaced relatively by an amount equal to the line time but this displacement has not been shown in the curves. It will be noted that Where impulses of greaterl than unit length occur such as from (a) to (d) and from (j) to (n), appreciable current is received, but on the short or unit impulses of alternately opposite polarity, such as occur between (d) and (f), (f) and (la), and (h) and (j), a very small current is received.
  • Curves 29 and 30 represent the positions of the relay tongues on the main vi brating relay MVR and the auxiliary vibrating relayAVR, respectively, at any instant of time, plus values indicating that the tongue lies against its right contact and minus values indicating that the tongue lies against its left contact.
  • the curve 31 indicates the impulses applied to the printing magnets 22 to 26 inclusive.
  • brush 32 again makes contact on a segment 2 and applies negative current through segment .2, resistance 4, resistance 8, Winding VW of the main vibrating relay, contact l() and tongue 13 of the auxiliary vibrating relay to positive battery. This results in l an electron flow from right to left and moves tongue 18 to the left, since, as shown at curve 28, the current in the line winding has become zero.
  • printing rings 'PR are represented on the receiving distributor comprising the common ring 20 and a segmental ring each segment of which is connected to a printer magnet.
  • the Baudot code comprising live unit pulses is used, and live printer magnets 22 to 26 inclusive have been shown as representing the equipment for one channel. It is expected that a system of the type described may comprise a number of channels but the printer equipment for each channel would be similar to that shown.
  • Printer magnets or relays 22 to .26 are of the conventional type, each having a normal and an operated position, the normal position corresponding to a negative signal impulse and the operated position to a positive signal impulse. When operated, the relays lock up until brush 33 has passed over allrfive segments in a channel and the recorded code character is printed, after which the-locked up relays are automatically restored to normal position.
  • the common return from printing magnets 22 to 26 in the first channel is connected to contact 16 of relay MVR, and the common printing ring 20 is connected to negative battery.
  • Brush 33 moves synchronously with brush 32 and as shown by the curves in Fig. 2 the tongue ot' the main vibrating.
  • relay MVR moves in synchronism with the transmitted signals shown in curve 27.
  • the common return conductor from the printing magnets (only four of which are shown) of the secondchannel is connected to contact 17 instead of contact 16 on relay MVR.
  • the common return conductor from alternate channels would be connected together.
  • the result of connecting the common return conductor from channel two, (and all even numbered channels) to contact 17 of' relay MVR is to invert the impulses applied to the printing relays in those channels. This is doneto correct for corresponding inversions or reversals of polarity at the transmitting station, known as channel reversals, which are customarily made in order that synchronizing impulses may be transmitted when no signals are being sent.
  • ARR represents an auxiliary repeating relay which is a double winding, polar relay similar to auxiliary vibrating relay AVR. These two windings are connected in series aiding relation and the midpoint connected to negative battery while the two terminals36 and 37 are connected to contacts 16 and 17 respectively of the main vibrating relay MVR.
  • Vhat is claimed is:
  • AO system in accordance with claim 1 having a circuit operatively connected to one of said relays to control its operation under the iniluence of electrical waves supplied by an external source which circuit when properly energized prevents one of said relays from operating the other.
  • a synchronous vibrating relay system comprising polar relays and a rotary disits lett contact.
  • a synchronous telegraph system two polar relays, each having an energlzmg windwmdang on the other ing, a movable armature and two opposing contacts cooperating therewith, a synchron-' ous distributor having a vibrating ring with a synchronously driven brush, characterizedy in this, that the armatures of both relays are connected to one terminal of a source of current, the other terminal of which is connected to the vibrating ring distributor brush, and that the energizing circuit for each relay winding comprises a distributor segment and the armature and a contact of the other relay.
  • a ynchronous distributor having a common ring and a segmented ring, alternate segments of which are connected together, a main reeach of said relays having a vibrating winding connected to the relay, a thirdconfixed-contacts 'of the other relay, a third ective mid-pointof the vibrating winding of one of said yrelays to one of said connected group of al- Tffternate distributor segments, an a connection from the effective midpoint of the vibrating relay to the second group ⁇ rof. alternate'distributor segments, a source of potential connected between said common ldistributor ring and the movable printer magnets connected between the segments of said ring and a fixed Contact of one of said relays,

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Accessory Devices And Overall Control Thereof (AREA)

Description

Oct 8, 1929. w. A. KNOOP 1,730,614
SYNGHRONOUS VIBRATORY RELAY SYSTEM Filed Oct. 26, 1927 /NVEA/mf? WML/AMA. /f/voop A Trap/vn Patented Cet. 8, 1929 PATENT @FMC WILLAM A. KNOOP, 0F HEMPSTEAD,
LABORATORIES, INCORPORATED, 0F NEW YORK, N.
YORK
NEW YORK, ASSIGNOR TO BELL TELEFHGNE SYNCHRONOUS VIBRATORY RELAY SYSTEM Application nl ed October 26, 1927. Serial No. 228,706.
This invention relates to high speed synchronous telegraph systems in which short signal impulses are excessively attenuated and must be rebuilt, or regenerated, at the receiving station, and its object is to simpliy and increase the reliability of thepequipment at the receiving station for rebuilding short signal impulses.
ln a telegraph system it is customary to transmit current impulses of diiierent length and polarity in various combinations to represent diiierent signal characters. Due to the excessive attenuation ot high frequency waves on long transmission lines, the short impulses are sometimes attenuated to apoint where they cannot operate the receiving line relay although longer impulses are received with ample strength to control the relays.
To make possible signaling under lsuch conditions, synchronous vibrating relay systems comprising relays, special rings on the synchronous receiving distributor, and sometimes auxiliary apparatus such as condensers, have been employed. These restore,
the receiving station, the short impulses that have been lost in transmission. rlhe systems heretofore used have usually required either a multiplicity of polar relays or the use on the receiving distributor of several rings,
' lng distributor.
or ofytwo segmented rings with special 1nsulating segments inserted between the live segments on one ring and in all cases it was customary to connect the opposite contacts of vsome of the polar relays to battery potential of opposite polarity, which necessitated the insertion of protective resistances in the battery leads 'to avoid danger of short-circuits from faulty adjustment of the relays. With protective resistances in the battery leads an extra relay was required to repeat the impulses to-a printing distributor.
The present system eliminates the necessity of using, in a vib'ratory relay system, more than two polar relays and more than one lain and one segmented ring on the receiv- Furthermore, in rthis system the necessity of connecting opposite contacts of a relay to sources of current of opposite polarity has been eliminated; therefore rotective resistances are not required in the attery leads, and as a result no separate printing relay is required.
The invention, in preterre'd embodiments, will now be described and its operation eX- plained in connection with the drawing in which:
Fig. 1 represents a complete system for the regeneration and printing of signal impulses -received over a telegraph conductor;
. Fig. 2 contains curves illustrating the operation of the apparatus in Fig. l; and
Fig. 3 illustrates an alternative arrangement for repeating impulses to another line.
Referring to Fig. 1, the vibrating relay circuit proper comprises a main vvibrating relay MVR and auxiliary vibrating relay AVR, vibrating rings VR, on a receiving distributor, and the circuit shown in heavy lines. Both MVR and AVR are high speed polar relays with two independent windings on each so disposed that an electron flow from left to right moves the associated relay tongue to the right and an electron flow from right to left moves the associated tongue to the left. rl`he two windings on the main vibrating relay MVR function independently of each other, the upper winding LW being the line winding, which may be connected to the telegraph conductor L1 through an amplifier as shown, and the lower winding VW forming a part of the vibrating circuit. It should be particularly noted that the operating current for the lower winding VW is limited by resistance 7 or resistance 8 to such a low value that the operation of the relay is controlled by the line winding LW, whenever a signal impulse of any substantial magnitude is received over the line conductor L1.
- Resistances 3 and 4 are` for contact protection only and do not need to be considered in following the operation of the system. Likewise resistances 14 and l5 shunted across the windingspf relay AVR are to improve the operating characteristics of that relay and may be disregarded. l
An explanation of the operation of the circuit shown in Fig. 1, in connection with the curves of Fig. 2 will now be made. These curves represent conditions theoretically.
Curve 27 represents the form of the wave transmitted from a distant station on conductor L1, while curve 28 represents the form of the received current after it is amplilied and applied to the line winding LW of the main vibrating relay. Curves 27 and 28 would actually be displaced relatively by an amount equal to the line time but this displacement has not been shown in the curves. It will be noted that Where impulses of greaterl than unit length occur such as from (a) to (d) and from (j) to (n), appreciable current is received, but on the short or unit impulses of alternately opposite polarity, such as occur between (d) and (f), (f) and (la), and (h) and (j), a very small current is received. Curves 29 and 30 represent the positions of the relay tongues on the main vi brating relay MVR and the auxiliary vibrating relayAVR, respectively, at any instant of time, plus values indicating that the tongue lies against its right contact and minus values indicating that the tongue lies against its left contact. The curve 31 indicates the impulses applied to the printing magnets 22 to 26 inclusive.
Assume at instant of time (A) that a long positive impulse has been transmitted over the line conductor L1, and is holding the main vibrating relay MVR againstits right contact as shown in Fig. 1. At this time brush 32 makes contact with segment 1 and applies negative current from the common ring 19 through resistance 3, through upper winding 5 of the auxiliary vibrating relay AVR,
through contact 16 and relay tongue 18 of MVR to positive battery. This results in an electron liow from right to left through the upper winding of AVR and the tongue 13 is held against left contact 10 as indicated atv curve 30. No current flows through tongue 13'and the vibrating winding VW of MVR at this time, but 'at time (B) brush 32 closes a circuit from segment 2 through resistance 4, resistance 8, winding VW and contact 1 0 to tongue 13 and positive battery. This re sults in an electron flow to the left through winding VW of MVR, but the relay does not operate because as shown by curve 28, the line current in the line winding Ll/V still controls the relay.
At time (C)` conditions are the same as they were at time (A) and a circuit is again closed causing an electron flow to the left through the upper winding of auxiliary vibrating relay AVR which of course tends to hold the tongue in the position it is already 1n.
At time (D) brush 32 again makes contact on a segment 2 and applies negative current through segment .2, resistance 4, resistance 8, Winding VW of the main vibrating relay, contact l() and tongue 13 of the auxiliary vibrating relay to positive battery. This results in l an electron flow from right to left and moves tongue 18 to the left, since, as shown at curve 28, the current in the line winding has become zero.
At time (E) brush 32 again closes on a segment 1, applying' negative potential to theV midpoint of the auxiliary vibrating relay AVR and, since tongue 18 of MVRis closed on contact 17, causes a flow of electrons from .left to right throughthe lower winding 6 of AVR, which moves the relay tongue 13 to the right against contact 12 as shown in curve 30.
At time (F) when brush 32 again makes contact on a segment 2, negative current is applied through resistances et and 7, winding VV of MVR, conductor 12 and tongue 13 of the auxiliary vibrating relay to positive battery. This electron flow to the right through winding VW of MVR moves the tongue 18 to the right against contact 16, since as shownl curve 30. It Will be seenthat as long as unit impulses of alternately opposite polarity are transmitted from the distant station, no current of controlling strength will be received in the line winding LW of the main vibrating relay MVR and the relay system will automatically vibrate to rebuild the unit impulses. The operation already followed through is repeated periodically until time (L), at which time, as shown by curve 28, an impulse greater than unit length has been transmitted from the distant station and a current of controlling strength is flowing in the line winding LTV of the main vibrating relay MVR. Therefore, when brush 32 applies negative current through a segment 2, resistance 8, winding VW of MVR, contact 10 and tongue 13 of the auxiliary vibrating relay, tongue 18 of the main vibrating relay does not move to the left as it did at time (D), because of the controlling action of the current in the line Winding LW'. Therefore, at time (M) negative current is still flowing from right to left thro-ugh the upper winding of the auxiliary .vibrating relay AVR and the armature AVR and contact I-Ieretofore no description has been given of the actual recording of the received and regenerated signals. In Fig. 1 printing rings 'PR are represented on the receiving distributor comprising the common ring 20 and a segmental ring each segment of which is connected to a printer magnet. In the system shown, the Baudot code comprising live unit pulses is used, and live printer magnets 22 to 26 inclusive have been shown as representing the equipment for one channel. It is expected that a system of the type described may comprise a number of channels but the printer equipment for each channel would be similar to that shown. Printer magnets or relays 22 to .26 are of the conventional type, each having a normal and an operated position, the normal position corresponding to a negative signal impulse and the operated position to a positive signal impulse. When operated, the relays lock up until brush 33 has passed over allrfive segments in a channel and the recorded code character is printed, after which the-locked up relays are automatically restored to normal position. The common return from printing magnets 22 to 26 in the first channel is connected to contact 16 of relay MVR, and the common printing ring 20 is connected to negative battery. Brush 33 moves synchronously with brush 32 and as shown by the curves in Fig. 2 the tongue ot' the main vibrating. relay MVR moves in synchronism with the transmitted signals shown in curve 27. Therefore, whenever positive impulses are transmitted from the distant station, the tongue of the main vibrating relay lies to the right and as brush 33 closes on a printing segment there is a flow of current from negative battery over ring 20, brush 33, through the printing magnet to contact 16 and positive battery connected to tongue 18. Therefore, at time (A) when a positive impulse is transmitted, tongue 18 will apply an operating impulse to printer magnet 22. At time (C), a positive impulse is still being transmitted from the distant station and an impulse is applied to printer magnet 23. At time a negative impulse is transmitted from the distant station and since the tongue 18 of the main vibrating relay lies to the left, a circuit is not closed for the operation of printer magnet 24 and it remains in normal position. Again, at time (G), a
positive impulse is transmitted from the distant station and an impulse is applied by tongue 18 of the main vibrating relay to printer magnet 25. At time (I), a negative impulse is transmitted from the distant station, tongue 18 lies against its left contact and printer magnet 26 remains in normal position.
It will be noted that the common return conductor from the printing magnets (only four of which are shown) of the secondchannel is connected to contact 17 instead of contact 16 on relay MVR. With more than two chan- `tongue 18 of the nels the common return conductor from alternate channels would be connected together. The result of connecting the common return conductor from channel two, (and all even numbered channels) to contact 17 of' relay MVR is to invert the impulses applied to the printing relays in those channels. This is doneto correct for corresponding inversions or reversals of polarity at the transmitting station, known as channel reversals, which are customarily made in order that synchronizing impulses may be transmitted when no signals are being sent.
The system described above eliminates the necessity of using a special printing relay between the main vibrating relay and the printing rings of the distributor, but such a relay may be inserted if desired, or, a repeating relay may be inserted to retransmit the regenerated signal impulses to another line. In Fig. 3 ARR represents an auxiliary repeating relay which is a double winding, polar relay similar to auxiliary vibrating relay AVR. These two windings are connected in series aiding relation and the midpoint connected to negative battery while the two terminals36 and 37 are connected to contacts 16 and 17 respectively of the main vibrating relay MVR. Since the tongue 18 of main vibrating relay MVR is connected to positive battery, there will be an electron flow from right to left through the upper winding ot ARR, when tongue 18 of MVR lies against its left contact f 17, and it will move tongue 38 of ARR against On the other hand, when main vibrating relay lies against its right contact 16, there will be an electron flow from left to `right through the lower winding of ARR which will move tongue '38 to the right. Thus the tongue of relay ARR follows the movements of the tongue of the main vibrating relay. Itn the opposite contactsof the auxiliary printing relay ARR are connected to negative and positive battery respectively, as shown in Fig. 3, and the tongueg38 connected to a second line L2, im-
ulses received over line L1 will be regenerated by the vibratingrelay system and retransmitted over L2.
Vhat is claimed is:
1. In a synchronous vibrating relay system. two polar relays, an operating source connected to the movable contacts of said relays, and means whereby each of said relays functions to operate the other as a result of its own operation.
2. AO system in accordance with claim 1 having a circuit operatively connected to one of said relays to control its operation under the iniluence of electrical waves supplied by an external source which circuit when properly energized prevents one of said relays from operating the other.
3. A synchronous vibrating relay system comprising polar relays and a rotary disits lett contact.
with their connecting circuits, the entire control means for controlling the vibration of said relays. v
' 4; In a synchronous normally vibrating relay system comprising two polar relays, two
f similar, equally spaced segments, traversedby contacts of sald relays, a llne Windlng on said vmain v1brat1ng relay, prlntlng rlngs on said distmhutor comprising a segmented ring with operating windings for each of said relays, a segmented ring for controlling said relays, and means for applying an electromotive force of the same said ring in succession.
5. 'In al synchronous 4vibrating relay system comprising a polar relay, havingl an energizing winding, the method of vibrating said relay with successive current impulses of likel polarity, which comprises applying lsaid suc-y p cessive impulses of like polarity through diffl ferent portions of the energizing and in opposite directions. y 6. In a synchronous telegraph system two polar relays, each having an energlzmg windwmdang on the other ing, a movable armature and two opposing contacts cooperating therewith, a synchron-' ous distributor having a vibrating ring with a synchronously driven brush, characterizedy in this, that the armatures of both relays are connected to one terminal of a source of current, the other terminal of which is connected to the vibrating ring distributor brush, and that the energizing circuit for each relay winding comprises a distributor segment and the armature and a contact of the other relay.
7 In a synchronous vibrating relay system, vL a main relay and an auxiliary relay, each vhaving a movable armature bearing a'contactfandf and v,angelje'rafcin'g"; f Winding on each relay connected be'twefs1.the`
opposing contacts therefore,
opposing contacts of the other'relay, a circuit for energizing eachwinding comprising-asource of electrical energy, and 'synchronous switching means, connected in 'seriesbetween the movable contact of each relay-and the operating winding of the other-relay, al line polarity to each segment of Y lay and an auxiliary relay,
rfixed contacts of the other V,connection from the eli able between two fixed contacts, said armature being connected to one terminal of a source of electrical energy, a group of printing magnets each having two operating terminals, one of which is connected to one of said fixed contacts, and means for periodically connecting the other terminal of each printing magnet to. the opposite terminal of said source of electrical energyein synchrox'r, ism with received signals.
10. In a telegraph receiving system a ynchronous distributor having a common ring and a segmented ring, alternate segments of which are connected together, a main reeach of said relays having a vibrating winding connected to the relay, a thirdconfixed-contacts 'of the other relay, a third ective mid-pointof the vibrating winding of one of said yrelays to one of said connected group of al- Tffternate distributor segments, an a connection from the effective midpoint of the vibrating relay to the second group `rof. alternate'distributor segments, a source of potential connected between said common ldistributor ring and the movable printer magnets connected between the segments of said ring and a fixed Contact of one of said relays,
polarity as that impressed upon the common 'vibratlng ring, a synchronously moving lbrush bridging the common vibrating ring lto the segmented vibrating ring, and a second 'synchronously moving brush, bridging the common prlntlng. ring to the lsegmented In witness'whereof, I hereunto subscribe lmy name this 24th day of October, A. D1 1927.
, WILLIAM A. KNOOP.
i winding on said main relaya'ndv printing'v means operated I.in response .to 'current su plied through the movable contact of themaln relay.
ceiving relay having a fixed Contact and a contact movable 1n response to received slgnalswhereby it makes electrical connectionwith the fixed contact, an operating circuit for said relay extending through a distributor and a winding of said relay, printing mag-*- 8. In a telegraph receiving system, a re# A a common printingring con- 4nected -toa source of potential of the same
US228706A 1927-10-26 1927-10-26 Synchronous vibratory relay system Expired - Lifetime US1730614A (en)

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GB550228A GB312209A (en) 1928-02-21 1928-02-21 Improvements relating to cable telegraphy

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2433362A (en) * 1942-03-13 1947-12-30 Standard Telephones Cables Ltd Pendulum relay controlled startstop telegraph transmitter

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2433362A (en) * 1942-03-13 1947-12-30 Standard Telephones Cables Ltd Pendulum relay controlled startstop telegraph transmitter

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