US2481607A - Automatic keyer for code transmitters - Google Patents

Automatic keyer for code transmitters Download PDF

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US2481607A
US2481607A US626143A US62614345A US2481607A US 2481607 A US2481607 A US 2481607A US 626143 A US626143 A US 626143A US 62614345 A US62614345 A US 62614345A US 2481607 A US2481607 A US 2481607A
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relay
conductor
contact
circuit
switch
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Mcgoffin William Walter
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L15/00Apparatus or local circuits for transmitting or receiving dot-and-dash codes, e.g. Morse code
    • H04L15/04Apparatus or circuits at the transmitting end
    • H04L15/22Apparatus or circuits for sending one or a restricted number of signals, e.g. distress signals

Definitions

  • This invention relates to an automatic transmitting device for transmitting code signals to the input of a circuit to be pulsed.
  • An object of this invention is to provide an automatic electrically operated keyer or transmitter, which includes a plurality of relays which are so arranged and constructed as to provide for the transmission of Morse Code signals, the device being formed with a plurality of selectively adjustable switches so that code signals of desired type may be repeatedly transmitted.
  • Another object of this invention is to provide an automatic keyer which includes an improved means for repeating the selected signal combination.
  • a further object of this invention is to provide an automatic keyer of this type wherein the controlling relays may be of the type which will be delayed in releasing the armature, so as to form the necessary dashes or, if desired, the slow action or release of the relays may be effected through electrical discharge condensers which are charged at the time the relays are energized and hold the charge a suificient degree to form the necessary dash. It is, of course, understood that slow releasing relays are of conventional type and where desired such slow releasing relays may be used in certain portions of the circuits to be hereinafter described in place of quick releasing relays having discharge condensers connected thereto.
  • Figure 1 is a diagrammatic view of an automatic keyer constructed according to an embodiment of this invention.
  • FIG. 2 is a fragmentary diagrammatic View of a modified form of this invention.
  • l designates generally a selector switch structure which embodies a plurality of stationary contacts l2, I3, l4, l5, l6, l1 and I8.
  • a movable switch arm I 9 is adapted to progressively engage the contacts H to l8 being mounted on a shaft 20.
  • the shaft 20 has ratchet 2
  • the pawl 22 is carried by a pivoted armature 23, which is spring pressed away from a r l wh t relay i e i ed the armature 23 will be drawn thereto and the shaft 20 rotated to swing the movable contact arm or wiperv l9 progressively from one stationary contact to the other.
  • relay 24 is energized armature 23 will be drawn thereto and pawl 22 will turn ratchet 2
  • a timing structure embodying a pair of relay members 25 and 26 is connected to the relay 24 and the timing structure includes an armature 21 associated with the relay 25, which is connected by means of a conductor 28 to one side of the relay 24.
  • the armature 21 is normally spring pressed away from a stationary contact 29, which is connected to one side of a supply source.
  • a second armature 30, which is connected to one side of the supply source, is insulated from armature 21 and is normally spaced from a stationary contact 3
  • a resistor 33 is interposed in the conductor 32.
  • An armature 34 is associated with the relay 25 bein connected to one side of the supply source and is normally spring pressed to engage a stationary contact 35, which is connected by a conductor 36 to one side of the relay '25.
  • Aresistor 31 is interposed in the conductor 36.
  • the other side of the relay 25 is connected by a conductor 38 to the other side of the supply source and a conductor 39 connects the other side of relay 26 to conductor 38.
  • An electricalcondenser, 40 is connected across the ends of the relay 25 and is of such capacity as to provide for the slow releasing of the armatures 30 and 21 when the circuit to the relay 25 has been broken.
  • is connected across the ends of the relay 26 and is also adapted to provide for keeping the relay 26 energized after the circuit to the relay has been broken. The capacity of the condensers 40 and 4
  • a plurality of selectively adjustable switches 42, 43, 44, 45, 46, 41, 48 and 49 are connected to the stationary contacts H to
  • Movable switch arm 50 is connected by conductor 5
  • Movable switch arm 54 is connected by conductor 55 to contact l3 and movable contact 56 is connected by conductor.51 to contact 4.
  • Movable contact 58 isconnected by conductor 59 to contact l5 and movable contact lill is conngcted by conductor 6
  • Movable contact 62 is connected by conductor 63 to contact I 6 and movable contact 64 is connected by conductor 65 totcontact I8.
  • the switches 42 to 49 inclusive are of like construction and each includes a blank contact 66 and contacts 61, 68, 5 69 and I0.
  • Contact 61 is connected to a dash circuit being connected to conductor II and contact 68 is connected to a space circuit being connected to copd ictgr 12.
  • r v r 1 "oiingeqeglto azho'ld circuit being 10
  • Contact 69115 connected to conductor' w. contactlwis' connected to a home circuit being connected'to conductor 14.
  • the cpnductor is
  • a conductor I0! is connected at one end to conductor 81 and at the other end is connected to conductor 32 between the resistor 33 and relay 26;
  • a condenser I 08 is interposed in conductor I01.
  • Armature I I t is connected bynneans of anarin I-I'51to a holding pawl 4 1s whionnonnany ngages; T 'coiinects arina re? 1 Z-Zd 'sbfthaE-when armature 'I M" is i die; to a'rd rlay l l Z'Fh'olding dog'il ls will be” rocle gainst the ension or spring "I l 8 and at the is' ame t-im'e -D aWI 2 2d will 7-5 rocked away from ratchet 2Ia thereby releasiii shaft '20:; Tfor fcoiinterciockwise rotation' by the spring l I 9.
  • switches 542 Etc 49 are pre'set tb p'rovijde 'tlie de sired output impulses and the-main controlling switch] B9imay th en' be closed.”
  • *With' switch -I BQ' closed :relay25 isenergizediclbsing'"tli circiiit tc I9:over:the'p0in'ts;dr contact I1 to' I 8.
  • Thej rlay; 26 :iSJtheintervalhelayythait 1s .the'rela'y' ulatihg' the interval betweenltheidots and dashes n'd this;
  • relay 25 When the energy of condensers I6 and 40 are discharged relay 25 will be deenergized and relay 26 will provide the necessary interval between the space and the next selected impulse which in this instance is a dash.
  • stepper arm I9 moves to contact I4 a circuit is broken through conductor 51 and switch arm 56 to conductor 1 I. The circuit then is completed through conductor 15 and condenser I6 to relay 25 and the latter will be maintained energized for the space of a dash while at the same time the key circuit will be closed by relay 25 through closing of the switch embodying the contacts BI and 92.
  • stepper arm I9 moves to contact II, which is connected by conductor 63 to switch 48 and the latter has the switch arm 62 connected to the hold circuit
  • relay 18 will be energized and condenser I06 will receive energy for maintaining relay I8 energized for a period after the breaking of the circuit through condenser I3 to relay I8.
  • Energizing of relay 18 will close the key circuit through armature I03 and contact I04.
  • stepper arm I9 is rotated to engage contact I8, which is connected by conductor 65 to switch arm 64 of switch 49.
  • the switch arm 64 is engaged with the home contact connected to conductor 14, so as to thereby energize relay 84.
  • relay B4 When relay B4 is energized the key circuit is broken through separation of armature 91 and contact 98.
  • the relay 25 will operate rapidly by draining of the electrical energy stored by condenser 40 through condenser 88.
  • the relay 25 will thereupon operate in the manner of a vibrator so as to rapidly open and close the electric circuit to stepper relay 24 and cause the stepper arm to rapidly rotate to the beginning of the letter sequence.
  • the resistors 33, 31 and I02 are provided to suppress spark in the several switches.
  • the automatic keyer as hereinbefore described will provide a simple keyer for code transmitters wherein any selected code characters can be transmitted without interchanging any of the elements in the system, such as in prior devices where code wheels are used for determining the particular letter or characters which are to be transmitted.
  • a device as hereinbefore described there may be as many manual switches as may be desired so as to provide for transmission of one or more letters and any number of characters in such letters.
  • the particular code or letter transmitted can quickly be changed by variation of the switch positions. As long as switch I09 is closed the characters transmitted will be repeated.
  • relays are disclosed in the drawing as being of conventional construction having discharge condensers connected thereacross, but it will be understood that these relays may be of various types suitable for the purpose, which are slow closing or slow releasing.
  • the switch embodying the armature 99 and the contact I00 which is connected from the positive through conductor IN to conductor I5 is provided in order to maintain the discharge condenser I6 electrified for transfer of the electrical charge to the relay 25.
  • An automatic keyer comprising a key circuit, a plurality of switches in said circuits, a stepper switch, a relay operator for said stepper switch, a plurality of relay operators for said first named switches, a plurality of manually adjustable switches connected to said stepper switch and said latter named operators, electromagnetic timing means connected to said stepper operator and certain ones of said first named switches, and means connected with said adjustable switches whereby said stepper switch operator may be rapidl vibrated to effect movement of said stepper switch to starting position when said stepper switch has moved through the operating cycle the length of which is determined by the adjustment of a particular one of said adjustable switches.
  • An automatic keyer comprising an output circuit, a plurality of input circuits, a plurality of switches connecting said input circuits to said output circuit, a plurality of adjustable switches connected to said input circuits, an electromagnetic stepper means connected to said latter switches, electromagnetic timing means connected to said stepper means, a discharge condenser connected across said timing means, a return circuit connected to said adjustable switches and said timing means whereby to break said output circuit and effect rapid operation of said timing means whereby said stepper means will be rapidly moved to starting position.

Description

Sept. 13, 1949. I w. w. M GOFFIN AUTOMATIC KEYER FOR CODE TRANSMITTERS Filed NOV. 1, 1945 Patented Sept. 13, 1949 AUTOMATIC KEYER FOR com-1 TRANSMITTERS 'William Walter McGolfin, New York, N. Y. Application November 1, 1945, Serial No. 626,143
2 Claims.
This invention relates to an automatic transmitting device for transmitting code signals to the input of a circuit to be pulsed.
An object of this invention is to provide an automatic electrically operated keyer or transmitter, which includes a plurality of relays which are so arranged and constructed as to provide for the transmission of Morse Code signals, the device being formed with a plurality of selectively adjustable switches so that code signals of desired type may be repeatedly transmitted.
Another object of this invention is to provide an automatic keyer which includes an improved means for repeating the selected signal combination.
A further object of this invention is to provide an automatic keyer of this type wherein the controlling relays may be of the type which will be delayed in releasing the armature, so as to form the necessary dashes or, if desired, the slow action or release of the relays may be effected through electrical discharge condensers which are charged at the time the relays are energized and hold the charge a suificient degree to form the necessary dash. It is, of course, understood that slow releasing relays are of conventional type and where desired such slow releasing relays may be used in certain portions of the circuits to be hereinafter described in place of quick releasing relays having discharge condensers connected thereto.
To the foregoing objects, and others which may hereinafter more fully appear, the invention consists of the novel construction, combination and arrangement of parts, as will be more specifically referred to and illustrated in the accompanying drawings, but it is to be understood that changes, variations, and modifications may be resorted to which fall within the scope of the invention as claimed.
In the drawing:
Figure 1 is a diagrammatic view of an automatic keyer constructed according to an embodiment of this invention, and
Figure 2 is a fragmentary diagrammatic View of a modified form of this invention.
Referring to the drawing, the numeral ||l designates generally a selector switch structure which embodies a plurality of stationary contacts l2, I3, l4, l5, l6, l1 and I8. A movable switch arm I 9 is adapted to progressively engage the contacts H to l8 being mounted on a shaft 20. The shaft 20 has ratchet 2| secured thereto with which a pawl 22 engages. The pawl 22 is carried by a pivoted armature 23, which is spring pressed away from a r l wh t relay i e i ed the armature 23 will be drawn thereto and the shaft 20 rotated to swing the movable contact arm or wiperv l9 progressively from one stationary contact to the other. When relay 24 is energized armature 23 will be drawn thereto and pawl 22 will turn ratchet 2| and shaft 20 one step in a clockwise direction. I
A timing structure embodying a pair of relay members 25 and 26 is connected to the relay 24 and the timing structure includes an armature 21 associated with the relay 25, which is connected by means of a conductor 28 to one side of the relay 24. The armature 21 is normally spring pressed away from a stationary contact 29, which is connected to one side of a supply source. A second armature 30, which is connected to one side of the supply source, is insulated from armature 21 and is normally spaced from a stationary contact 3| which is connectedby means of a conductor 32 to one side of the relay 26. .A resistor 33 is interposed in the conductor 32. An armature 34 is associated with the relay 25 bein connected to one side of the supply source and is normally spring pressed to engage a stationary contact 35, which is connected by a conductor 36 to one side of the relay '25. Aresistor 31 is interposed in the conductor 36. The other side of the relay 25 is connected by a conductor 38 to the other side of the supply source and a conductor 39 connects the other side of relay 26 to conductor 38.
An electricalcondenser, 40 is connected across the ends of the relay 25 and is of such capacity as to provide for the slow releasing of the armatures 30 and 21 when the circuit to the relay 25 has been broken. An electrical discharge condenser 4| is connected across the ends of the relay 26 and is also adapted to provide for keeping the relay 26 energized after the circuit to the relay has been broken. The capacity of the condensers 40 and 4| will determine the length of time therelays 25 and 26 will be maintained energized. A plurality of selectively adjustable switches 42, 43, 44, 45, 46, 41, 48 and 49 are connected to the stationary contacts H to |8 respectively and in each instance the movable switch arm or wiper is connected to the stationary contacts. Movable switch arm 50 is connected by conductor 5| to contact I and movable switch arm 52 is connected by conductor 53 to contact l2. Movable switch arm 54 is connected by conductor 55 to contact l3 and movable contact 56 is connected by conductor.51 to contact 4. Movable contact 58 isconnected by conductor 59 to contact l5 and movable contact lill is conngcted by conductor 6| to contact l6. Movable contact 62 is connected by conductor 63 to contact I 6 and movable contact 64 is connected by conductor 65 totcontact I8. The switches 42 to 49 inclusive are of like construction and each includes a blank contact 66 and contacts 61, 68, 5 69 and I0. Contact 61 is connected to a dash circuit being connected to conductor II and contact 68 is connected to a space circuit being connected to copd ictgr 12. r v r 1 "oiingeqeglto azho'ld circuit being 10 Contact 69115 connected to conductor' w. contactlwis' connected to a home circuit being connected'to conductor 14. Conductor H is' connected to a cori ductor I5 which at one end is coll'iffifi drt end of the relay 25 and a condenser 16 is =mter-; 15
posed in the conductor 15. The cpnductor]; is
connected to a spring pressedirihatiir Ta's' sociated with a relay I8. ififi'ieirmaititreiilliis i normally spaced from a stationary contact]? which is connected to idle positive side'of the sateen? Armature dl is c can? a d em s--- :6
i l his i lqili ncted"'byf ac tone.
i shown in Figure 1.
- gize'd condenser t I will buil '91, contact 98 and co duct is engaged with a stationary contact 69 of the latter switches. A conductor I0! is connected at one end to conductor 81 and at the other end is connected to conductor 32 between the resistor 33 and relay 26; A condenser I 08 is interposed in conductor I01. Conductor 38, which isconnected to the positive side of the supply source, has a main switch I09 interposed therein for regulating thev operation f the device. 7
"Referring noWZ tQ Fi 'there"s' disclosed a modified form of this invention which relates only {to the selector portion of the circuit structure In this modification the sezle'ctorswitcharm I9a is mounted on a shaft 26a, xwhich-has a coil spring I I0 secured at one end thereto, so that-;aiter switch arm I9a has wiped over the st'ationary contacts Ila, 12a, I3a, [4a, 1511, :Ifia'g" 151d; :tmwa'nd finally reaches a release contaetj LI, spring I ID will return switch arm I9a to"the"fi'rst"contact I la. ,The return of the switch arm Ilia is efiected as follows: BelayZfig which; is
zed rocks 1 II 3 to conductor 8-! showii iii condenser-88 and armatu therewith ali lflnatlllie l l-i.
Armature I I t is connected bynneans of anarin I-I'51to a holding pawl 4 1s whionnonnany ngages; T 'coiinects arina re? 1 Z-Zd 'sbfthaE-when armature 'I M" is i die; to a'rd rlay l l Z'Fh'olding dog'il ls will be" rocle gainst the ension or spring "I l 8 and at the is' ame t-im'e -D aWI 2 2d will 7-5 rocked away from ratchet 2Ia thereby releasiii shaft '20:; Tfor fcoiinterciockwise rotation' by the spring l I 9. In other'resp'cts' the circuit'arra'nge; ment'fof Figure l isfas'so ated' with'the autorhatgic I I 4 to ratchet ro ta releasing structure-shown in 'Figiirefl."
' In the operation of tliis de ice' theseveraI manual, switches 542 Etc 49 are pre'set tb p'rovijde 'tlie de sired output impulses and the-main controlling switch] B9imay th en' be closed." *With' switch -I BQ' closed :relay25 isenergizediclbsing'"tli circiiit tc I9:over:the'p0in'ts;dr contact I1 to' I 8. "Thej rlay; 26 :iSJtheintervalhelayythait 1s .the'rela'y' ulatihg'" the interval betweenltheidots and dashes n'd this;
tus :for the device; when-ma 25 -?is ene da 7 circuit win ibe fcompletedithroiighcontact?i 'to '7 relay 26 energizing relay and bi'eaking" the negativeside 'toreleiy 25;" when Iay'ZLB Zi s enerE after armature 3Iligi disengage 3|)" Thiswill p-rovide theta-teams w pulses, both dots and dashes.
energized the switch formed b having the V movable ected t th This relay, when energized, will break the circuit to the key circuit by drawing armatures 8| to 94 thereto. At this time the contacts BI and 82 will close the circuit through conductors 83 and I5 to discharge condenser 16, so that relay 25 will be maintained energized for the desired space while at the same time the key circuit is broken so that no impulse will be transmitted through the key circuit.
When the energy of condensers I6 and 40 are discharged relay 25 will be deenergized and relay 26 will provide the necessary interval between the space and the next selected impulse which in this instance is a dash. When stepper arm I9 moves to contact I4 a circuit is broken through conductor 51 and switch arm 56 to conductor 1 I. The circuit then is completed through conductor 15 and condenser I6 to relay 25 and the latter will be maintained energized for the space of a dash while at the same time the key circuit will be closed by relay 25 through closing of the switch embodying the contacts BI and 92. When stepper arm I9 moves to contact II, which is connected by conductor 63 to switch 48 and the latter has the switch arm 62 connected to the hold circuit, relay 18 will be energized and condenser I06 will receive energy for maintaining relay I8 energized for a period after the breaking of the circuit through condenser I3 to relay I8. Energizing of relay 18 will close the key circuit through armature I03 and contact I04. In the next sequence stepper arm I9 is rotated to engage contact I8, which is connected by conductor 65 to switch arm 64 of switch 49.
The switch arm 64 is engaged with the home contact connected to conductor 14, so as to thereby energize relay 84. When relay B4 is energized the key circuit is broken through separation of armature 91 and contact 98. At this time the relay 25 will operate rapidly by draining of the electrical energy stored by condenser 40 through condenser 88. The relay 25 will thereupon operate in the manner of a vibrator so as to rapidly open and close the electric circuit to stepper relay 24 and cause the stepper arm to rapidly rotate to the beginning of the letter sequence. The resistors 33, 31 and I02 are provided to suppress spark in the several switches.
The disclosure shown in Figure 2 will operate in the same manner as that shown in Figure 1 except that when the electric circuit is completed to the home circuit 14, relay H2 will be energized and stepper arm I9a will be released from the stepper dog 22a and the holding dog II6, so that this stepper arm can be rotated by the spring I I0 back to its starting position.
The automatic keyer as hereinbefore described will provide a simple keyer for code transmitters wherein any selected code characters can be transmitted without interchanging any of the elements in the system, such as in prior devices where code wheels are used for determining the particular letter or characters which are to be transmitted. In a device as hereinbefore described there may be as many manual switches as may be desired so as to provide for transmission of one or more letters and any number of characters in such letters. The particular code or letter transmitted can quickly be changed by variation of the switch positions. As long as switch I09 is closed the characters transmitted will be repeated.
The several relays are disclosed in the drawing as being of conventional construction having discharge condensers connected thereacross, but it will be understood that these relays may be of various types suitable for the purpose, which are slow closing or slow releasing. In the present circuit arrangement the switch embodying the armature 99 and the contact I00 which is connected from the positive through conductor IN to conductor I5 is provided in order to maintain the discharge condenser I6 electrified for transfer of the electrical charge to the relay 25.
The exact configuration illustrated is regarded as the optimum, but some of the desirable results inherent in this disclosure may be obtained by various slight modifications including some departure from the exact configuration shown, and it is therefore requested that the scope of the invention should be regarded as limited only by the terms of the claims.
What I claim is:
1. An automatic keyer comprising a key circuit, a plurality of switches in said circuits, a stepper switch, a relay operator for said stepper switch, a plurality of relay operators for said first named switches, a plurality of manually adjustable switches connected to said stepper switch and said latter named operators, electromagnetic timing means connected to said stepper operator and certain ones of said first named switches, and means connected with said adjustable switches whereby said stepper switch operator may be rapidl vibrated to effect movement of said stepper switch to starting position when said stepper switch has moved through the operating cycle the length of which is determined by the adjustment of a particular one of said adjustable switches.
2. An automatic keyer comprising an output circuit, a plurality of input circuits, a plurality of switches connecting said input circuits to said output circuit, a plurality of adjustable switches connected to said input circuits, an electromagnetic stepper means connected to said latter switches, electromagnetic timing means connected to said stepper means, a discharge condenser connected across said timing means, a return circuit connected to said adjustable switches and said timing means whereby to break said output circuit and effect rapid operation of said timing means whereby said stepper means will be rapidly moved to starting position.
WILLIAM WALTER MCGOFFIN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,136,838 Rugh Apr. 20, 1915 1,708,989 White Apr. 16, 1929 2,233,169 Jones Feb. 25, 1941 2,264,987 Kovalsky Dec. 2, 1941 2,300,935 Kovalsky NOV. 3, 1942 2,350,551 Fish et al June 6, 1944
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2558718A (en) * 1949-10-18 1951-07-03 William A Dougherty Code transmitter
US2645767A (en) * 1951-01-26 1953-07-14 Socony Vacuum Oil Co Inc Electromechanical interval timer
US2771600A (en) * 1953-07-22 1956-11-20 Link Aviation Inc Universal station identification signal keyer for use in grounded aviation trainers

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1136838A (en) * 1912-08-26 1915-04-20 Hall Switch & Signal Co Selective call device.
US1708989A (en) * 1929-04-16 Signaling system
US2233169A (en) * 1940-03-28 1941-02-25 Gen Electric Control system
US2264987A (en) * 1939-12-21 1941-12-02 Westinghouse Electric & Mfg Co Regulating apparatus
US2300935A (en) * 1938-01-13 1942-11-03 Westinghouse Electric & Mfg Co Rheostatic regulator
US2350551A (en) * 1941-12-22 1944-06-06 Edwin L Fish Electric switch apparatus

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1708989A (en) * 1929-04-16 Signaling system
US1136838A (en) * 1912-08-26 1915-04-20 Hall Switch & Signal Co Selective call device.
US2300935A (en) * 1938-01-13 1942-11-03 Westinghouse Electric & Mfg Co Rheostatic regulator
US2264987A (en) * 1939-12-21 1941-12-02 Westinghouse Electric & Mfg Co Regulating apparatus
US2233169A (en) * 1940-03-28 1941-02-25 Gen Electric Control system
US2350551A (en) * 1941-12-22 1944-06-06 Edwin L Fish Electric switch apparatus

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2558718A (en) * 1949-10-18 1951-07-03 William A Dougherty Code transmitter
US2645767A (en) * 1951-01-26 1953-07-14 Socony Vacuum Oil Co Inc Electromechanical interval timer
US2771600A (en) * 1953-07-22 1956-11-20 Link Aviation Inc Universal station identification signal keyer for use in grounded aviation trainers

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