US1298613A - Wireless signaling system. - Google Patents

Wireless signaling system. Download PDF

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US1298613A
US1298613A US2335215A US2335215A US1298613A US 1298613 A US1298613 A US 1298613A US 2335215 A US2335215 A US 2335215A US 2335215 A US2335215 A US 2335215A US 1298613 A US1298613 A US 1298613A
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antenna
circuit
transmitting
switch
normally
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US2335215A
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William C White
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General Electric Co
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General Electric Co
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40Circuits
    • H04B1/44Transmit/receive switching
    • H04B1/48Transmit/receive switching in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter

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  • My present invention relates to wireless 0 signaling systems and more especially to those adapted to transmit sound by means of electromagnetic waves set up in the ether.
  • the object of my invention is to provide such a system in which either receiving apparatus or transmitting apparatus is automatically connected to an antenna when desired.
  • the antenna 1 is normally connected to ground at 2 through the lower contact 3 of relay 4 and the usual variable inductance 5.
  • the receiving apparatus may be of any desired form. As here indicated it comprises an electron discharge device 6 haying a con- 7 trolling grid 7 which is inductively connected to the antenna by means of the coil 8.
  • a variable condenser- 13 is employed in the circuit of the grid 7 and cathode 10 for tuning.
  • the operating of receiving apparatus of this nature is too well known to require further description.
  • the transmlttlng apparatus which I employ in the present case comprises an elec tron discharge device 14 which may be so connected that it will produce continuous electrical waves of high frequency but which is normally inoperatlve.
  • the plate circuit of this device includes between cathode 15 and anode 16 a source of energy 17 and a coil 18 inductively related to the coil 19 and also to the coil 20 which is connected to the controlling grid 21 when contact 22 of relay 23 is closed. While the three coils 18, 19 and 20 may be inductively related to each other as indicated other arrangements may equally well be used as,.for example, a second coil may be employed in the antenna and coil 20 inductively related to this second coil.
  • the apparatus which I employ for this purpose comprises a telephone'transnutter 2?,an electron discharge device 28 which serves as an amplifier, and another electrondischarge device :29 which serves to control the amplitude of the oscillations in the grid circuit'of device 14.
  • the controlling device :29 has a source of energy 30 connected to its electrodes 31 and 32 and the plate circuit of this device also includes the winding of relay 'hen the produced in the plate circuit of the amplifier.
  • the variable current thus produced flows through transformer 37 and produces corresponding potential variations in the grid 38 of the controlling device 29, thereby reproducing in the plate circuit of the controlling device current variations corresponding to' those produced by the transmitter 27.
  • Vhen'relay 33 operates it makes contact at 39 and closes the local circuit of relay 40.
  • Relay 40 then operates and makes contact at 41 closing the local circuit of re lays I and 23, thereby disconnecting the receiving apparatus and connecting the transmit-ting apparatus to the antenna.
  • Relays 33 and 40 should be quick acting relays and relays 4 and 23 should be quick to close but should have an appreciable time lag in opening to prevent the transmitting apparatus from being disconnected during a momentary cessation of the sound waves actingupon transmitter 27. This time.
  • lag ispreferably greater for relay 4 than for relay 23 in order thatrelay 23 may open and thus stop the production of oscillations before the antenna circuit is broken at.
  • the winding of relay 33 is preferably shunted by a condenser 42 so that the alternating component of the current flowing in the plate circuit of the controlling device 29 will not have to pass through this winding.
  • the source of energy 30 may conveniently be employed for heating the cathodes 1'5 and 31 of ele'ctron'discharge devices It and '29 as indicated, the temperature of these being adjusted by the variable resistance 43. If desired the same source may be used for heat ing the cathodes of devices 6 and 28, al-
  • a wireless signaling system of an antenna. receiving apparatus normally connected to said antenna. trans- 3.
  • the combination 1n a wireless signaling system, of an antenna,- receiving apparatus normally connected to sald antenna, transmitting apparatus which is normally dis connected from the antenna, a telephone transmitter, a switch 'for disconnecting said qreceiving apparatus and connecting the transmitting apparatus to the antenna and means whereby the action of sound waves upon said transmitter causes said switch to operate.
  • a wireless signaling system-of means for producing continuous electrical oscillations comprising an elec tron discharge device having'a cathode, an anode and a discharge controlling grid, a normally open switch in the grid circuit of said device and means'actuated by sound waves to cause said switch to close.
  • a relay for controlling the operation of said switch, a telephone'transmitter-and'means whereby the action of sound waves upon said transmitter, will cause said relay to act and close saidswitch.
  • an antenna In a radio telephone system, an antenna, receiving and transmitting circuits, said antenna being normally connected to said receiving circuit, and means. controlled by the voice for automatically connecting said transmitting circuit to said antenna when said system is used for transmission.
  • an antenna In a radio telephone system, an antenna, receiving and transmitting circuits, and means controlled by the voice for automatically connecting said transmitting circuit to said antenna only when said antenna is used for transmission.
  • an antenna In a radio telephone system, an antenna, receiving and transmitting circuits, voice controlled means for automatically connecting said transmitting circuit to said antenna and means for automatically breaking said connection when transmission ends.
  • an an-v tenna normally connected to a receiving circuit, a normally open transmitting circuit, andmeans controlled, by sound Waves to antomatically close said transmitting circuit.
  • a receiving system a transmitting system and a common antenna therefor, a switch for connecting said antenna to either of said systems, and automatically operated voice controlled means for actuating said switch.
  • a radio telephone system a receivlng system, a transmitting system and a common antenna therefor, a sw1tch for connectlng said antenna to either of said systems, and volce controlled means for operating said switch, said means being operated by the closing of avnormally open circuit.
  • a radio telephone system In a radio telephone system, a receiving system, a transmitting system and a com- 111011 antenna therefor, a switch for connecting said antenna to either of said systems, and means for operating said switch. said means being controlled by a make and break circuit device and voice controlled means for operating said device.
  • a radio telephone system a receiving system, a transmitting system and a common antenna therefor, a switch for connecting said antenna to either of said systems, and means for operating said switch, said means being controlled by a make and break circuit device, operated by sound waves.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Transmitters (AREA)

Description

W. 0. WHITE.
WIRELESS SIGNALING SYSTEM.
APPLIQATIQN. EILED APR. 23| 1915- Patented Mar. 25,1919.
Inventor. bWilliam C.Wh'|ce,
3 Q His Atfiomeg wILmim- 0. Warm,
or". scnEN c'rAbY. new YORK. ASSIGNOB 'ro GENERAL ELECTRIC- COMPANY, A CORPORATION NEW YORK.
WIRELE SIGNALING SYSTEM.
Specification of Letters Patent.
Patented Mar. 25; 1919.
' Application filed April 23, 1915. Serial No. 23,352.
' To all Qohom it may concern:
Be it known that I, WILLIAM C. WHI rE,
acitizen of the United States, residing at Schenectady, in the county of Schenectady,
State of New York, have invented certain new and useful Improvements in Wireless Signaling Systems, of which the following is a specification.
My present invention relates to wireless 0 signaling systems and more especially to those adapted to transmit sound by means of electromagnetic waves set up in the ether.
The object of my invention is to provide such a system in which either receiving apparatus or transmitting apparatus is automatically connected to an antenna when desired. p
In carrying my invention into efiect I provide suitable receiving apparatus which '20 is normally connected to' the antenna. I
also provide a system of relays in connection with the transmitting apparatus which is automatically set' into operation, as soon as the transmitter is influenced by sound waves,
to disconnect the receiving apparatus from the antenna and connect the transmitting apparatus thereto; When the transmitter is no longer influenced by sound waves the transmitting apparatus is automatically disconnected and the receiving apparatus connected again to the antenna.
The features of my invention which I consider novel are pointed out with particularity in the appended claims. My invention itself, however, with further objects and advantages thereof will be 'best understood by reference to the following description taken in connection with the accompanying drawing in which I have illustrated diagrammatically a single embodimentthereof;
Q As indicated in the drawing, the antenna 1 is normally connected to ground at 2 through the lower contact 3 of relay 4 and the usual variable inductance 5. The receiving apparatus may be of any desired form. As here indicated it comprises an electron discharge device 6 haying a con- 7 trolling grid 7 which is inductively connected to the antenna by means of the coil 8. The circuit of the electrodes 9 and 10 of the electron discharge device 6, which for convenience of description I term the plate circuit, includes a battery 11 or other source of energy and a telephone receiver 12.
A variable condenser- 13 is employed in the circuit of the grid 7 and cathode 10 for tuning. The operating of receiving apparatus of this nature is too well known to require further description.
The transmlttlng apparatus which I employ in the present case comprises an elec tron discharge device 14 which may be so connected that it will produce continuous electrical waves of high frequency but which is normally inoperatlve. The plate circuit of this device includes between cathode 15 and anode 16 a source of energy 17 and a coil 18 inductively related to the coil 19 and also to the coil 20 which is connected to the controlling grid 21 when contact 22 of relay 23 is closed. While the three coils 18, 19 and 20 may be inductively related to each other as indicated other arrangements may equally well be used as,.for example, a second coil may be employed in the antenna and coil 20 inductively related to this second coil. When relayfi operates it breaks contact at 3 and makes a Second contact at 25, thus connecting coil 19 between the antenna and ground and disconnecting the re ceiving apparatus from the antenna. the transmitting apparatus connected to the antenna as described, and contact 22 closed, when current starts to flow in the plate circuit energy is transferred to the coil 20 and oscillations, are set up in the grid :circuit which includes the coil 20, grid 21*, cathode With 15 and variable condenser 26. These oscillations cause the potential of the grid'21 to vary. This variation in the grid potential in turn produces a variation in the current in-the plate circuit. When the poten- ;tial of the grid varies in a negative direction the current fiowingin the plate circuit decreases and when it varies in a positive direction the current flow in the plate circuit increases; These variations in the current in the. plate circuit produce an alternating current in the antenna and by varying the natural frequency of the grid circuit by varying the condenser 26 the frequency of a the alternating current be varied at will. When contact 22 is openthe grid 21 being disconnected from the, rest of the device, no oscillations will be produced and but little current will flow through device 14 by reason of the tendency of the grid 21 to become negatively charged. v
us produced may In order to transmit sound by means of such waves it is necessary to vary the amplitude of the waves transmitted in accordance with variations in the sound waves which are to be transmitted. This may bedone by varying the amplitude of the -oscillations produced in the grid circuit of devicel-l inaccordance with the variations in the sound waves. The apparatus which I employ for this purpose comprises a telephone'transnutter 2?,an electron discharge device 28 which serves as an amplifier, and another electrondischarge device :29 which serves to control the amplitude of the oscillations in the grid circuit'of device 14.
The controlling device :29 has a source of energy 30 connected to its electrodes 31 and 32 and the plate circuit of this device also includes the winding of relay 'hen the produced in the plate circuit of the amplifier. I The variable current thus produced flows through transformer 37 and produces corresponding potential variations in the grid 38 of the controlling device 29, thereby reproducing in the plate circuit of the controlling device current variations corresponding to' those produced by the transmitter 27. The
currentthus produced will of course be a pulsating current but the average value of it will be much greater than the normal current in the plate circuit of the controlling device and will be suflicient to operate the relay 33. Vhen'relay 33 operates it makes contact at 39 and closes the local circuit of relay 40. Relay 40 then operates and makes contact at 41 closing the local circuit of re lays I and 23, thereby disconnecting the receiving apparatus and connecting the transmit-ting apparatus to the antenna. Relays 33 and 40 should be quick acting relays and relays 4 and 23 should be quick to close but should have an appreciable time lag in opening to prevent the transmitting apparatus from being disconnected during a momentary cessation of the sound waves actingupon transmitter 27. This time. lag ispreferably greater for relay 4 than for relay 23 in order thatrelay 23 may open and thus stop the production of oscillations before the antenna circuit is broken at. 'hile I have indicated the telephone transmitter as being located close to the other apparatus it will be evident that it may equally well be connected thereto by a wire line of any length desired.
In the system I have described if the dc vice 29 is not connected to the grid circuit of device 14 this grid circuit will oscillate freely and the oscillations therein will have a substantially constant amplitude. 'hen, however, device 29 is connected as indicated to the grid circuit of device 14: some of the energy of the'high frequency oscillations will be diverted from the grid circuit through the controlling device and as a result the oscillations set up therein will be damped, the
amount of the damping of the oscillations of course depending upon the amount of energy diverted. The amount of energy thus diverted will vary in accordance with the variations in the potential of the controlling grid 38. As soon as energy is diverted from ythe grid circuit of device 14 and the oscillak tions therein are accordingly damped the current variations in the plate circuit of device 14: are correspondingly reduced and the high frequency currentset up in the antenna 1s reduced. Tlns in turn causes a further reduction in the amplitude of the oscillations in the grid circuit.
The winding of relay 33 is preferably shunted by a condenser 42 so that the alternating component of the current flowing in the plate circuit of the controlling device 29 will not have to pass through this winding.
The source of energy 30 may conveniently be employed for heating the cathodes 1'5 and 31 of ele'ctron'discharge devices It and '29 as indicated, the temperature of these being adjusted by the variable resistance 43. If desired the same source may be used for heat ing the cathodes of devices 6 and 28, al-
though to avoid. complications in the ,dia-
gram I have shown separate batteries l-l and 45 for this purpose. I also find it desirable to employ a condenser T6 in shunt to the source of supply 17 in order that the high frequency component of the current in the plate circuit of device 1t will not be required to pass through the supply source.-
Vhile I have illustrated a single embodiment of my invention I do not wish to be limited to the precise form described as it will be apparent toone skilled in the art that many modifications thereof may be made without departing from the scope of the appended claims. v
'hat I claim as new and desire to secure by Letters Patent of the United States. is
1. The combination in a wireless signaling system. of an antenna. receiving apparatus normally connected to said antenna. transmitting apparatus which is normally inoperative. and means whereby sound waves render said transmitting apparatus operative. automatically connect it to the antenna and disconnect the receiving apparatus.
- '2. The combination in a wireless signaling system. of an antenna. receiving apparatus normally connected to said antenna. trans- 3. The combination 1n a wireless signaling system, of an antenna,- receiving apparatus normally connected to sald antenna, transmitting apparatus which is normally dis connected from the antenna, a telephone transmitter, a switch 'for disconnecting said qreceiving apparatus and connecting the transmitting apparatus to the antenna and means whereby the action of sound waves upon said transmitter causes said switch to operate.
4. The combination in a wireless signaling system, of an antenna, receiving apparatus normally connected to said antenna, transmitting apparatus which is normally disconnected from the antenna, a telephone transmitter, a switch for disconnecting said receiving apparatus and connecting the transmitting apparatus to the antenna, a relay for controlling the operation of said switch and means whereby-the action of sound waves upon said transmitter causes said relay to act and operate said switch.
5. The combination in a wireless signaling system, of an antenna, receiving apparatus normally connected to said antenna, transmitting apparatus which is normally inoperative and disconnected from the antenna, a telephone transmitter, a switch for disconnecting said receiving apparatus and connecting the transmitting apparatus to the antenna, a. second switch for rendering the transmitting apparatus operative, arelay for controlling the operation of said switches and means whereby the action of sound waves upon said transmitter causes said relay to act and operate sald switches. 6. The combination in a wireless signahng system of an apparatus for producing continuous electrical waves which is normally inoperative, a switch for controlling the operation of said wave producing apparatus, and means actuated by sound waves to cause the closing of said switch to render said wave producing apparatus operative.
T. The combination in a wireless signaling system ofapparatusJfor' producing continuous electrical waves which isnormally in operative, 'a switch 'for controlling theopers ation of said wave producing apparatus, a
telephone transmitter, and means whereby the action of sound wavesfupon said trans- 'mi'tterj will cause said switch to close and vrender said wave Q 1'oduc1ngapparatus op: erative. r
8; The coinbinatioii in a wireless signaling system ']of apparatusQfor producing ,fcontinuous elec'tritfalfwaves which 1st normally 1noperative, a switch for rendering said wave producing apparatus operative, a relay for controlling the operation of said switch, a telephone transmitter and means whereby the action of sound waves upon said transmitter will cause said relay to act and operate said switch.
9, The combination in a wireless signaling system-of means for producing continuous electrical oscillations comprising an elec tron discharge device having'a cathode, an anode and a discharge controlling grid, a normally open switch in the grid circuit of said device and means'actuated by sound waves to cause said switch to close.
10. The combination in a wireless signaling system of means for producing continuous electrical oscillations comprlsing an electron discharge device having a cathode,
-normally open switch in the grid circuit of said device, a relay, for controlling the operation of said switch, a telephone'transmitter-and'means whereby the action of sound waves upon said transmitter, will cause said relay to act and close saidswitch."
'12. The combination in a wireless signaling system of an antenna, transmitting ap paratus which is normally inoperativeand disconnected from the antenna,a switch for connecting said transm tting apparatus to the antenna, a second switch for rendering the transmitting apparatus operative, re-
lays to close said switchesand hold thesame closed 'for an appreciable e iod after the] force actuating the" relaysf-isfwithdrawn,
and means rendered operative by, sound waves for operating said'relays. a,
13. The combination in a wirelessfsignal-j ing system of an antenna, transmitting ap paratus which isnormally disconnectedifrom the antenna, a switchffor connecting said transmitting apparatus 1 relay to close'saidjswitch ouickly and hold" it closed a for an appreciable interval after and means] renderedf operative by spund' 14:. The combination in' a wireless jsi'g nal waves "for actuating saidlrelay,
ing system of an antenna,' normally"inopcratiye means for prod'ucijn'g cont nuous elem to the antenna, a
i a a at ng:t erelay thd wn;
tribal Wa n d? ante nml s bh f r? 1 I I S- l 1. 7 ic er i ils e d swith ae -l e se ame" closed during the continuance of the sound avaves for connecting said transmitting apparatus to said antenna.
16. The combination in a wireless signaling system of an antenna. transmitting apparatus which is normally disconnected from the antenna and means actuated bysound waves for connecting said transmitting apparatus to the antenna and holding it in that relation during the continuance of the sound waves.
17. The combination of normally inoperative nieans comprising an electron discharge device for producing continuous electrical waves and means comprising a second electron discharge device for rendering the wave producing means operative and varying the amplitude of the waves produced thereby.
18. The combination in a wireless signaling system of normally inoperative'means for producing continuous electrical waves comprising an electron discharge device and means comprising a second electron disducing means operative and varying the amplitude of the waves produced thereby.
19. The combination in a wireless signaling system of an antenna, normally inoperative means comprising an electron discharge device for producing continuous elec: trical waves in said antenna, and means comprising a second electron device for rendering said wave producing device operative and varying the amplitude of the waves produced thereby in accordance with variations in sound waves.
1 20. The combination with norinally inop- .erative means comprising an electron discharge device for producing continuous electrical waves, of means for rendering said wave producing means operative and varying the amplitude of the waves produced thereby.
21. The combination in a wireless signaling system of an antenna, means comprising an electron discharge device for producing continuous electrical waves in said antenna, said means being normally discons nected from said antenna and means for connecting said wave producing means to said antenna and varying the amplitude of the Waves produced thereby.
22. The combinationin a-wireless signaling system of an antenna. means comprising an electron discharge device for producing continuous electrical waves in said an tenna. said means being-normally disconnected from said antennaand means com- 56 prising a second electron discharge device charge device for rendering said wave pro for connecting said wave producing means to said antenna and varying the amplitude of the wavesproduced thereby.
23. The combination in a wireless signaling system of an antenna, transmitting apparatus which is normally disconnected from the antenna and means comprising an electron discharge device for automatically connecting said transmitting apparatus to said antenna.
24. The combination in a wireless signaling system of an antenna, transmitting ap paratus which is normally disconnected from the antenna and means comprising an electron discharge device for automatically connecting said transmitting apparatus to said antenna and-varying the signals transmitted in accordance with variations in sound waves.
:25. In a radio telephone system, an antenna, receiving and transmitting circuits, said antenna being normally connected to said receiving circuit, and means. controlled by the voice for automatically connecting said transmitting circuit to said antenna when said system is used for transmission.
26. In a radio telephone system, an antenna, receiving and transmitting circuits, and means controlled by the voice for automatically connecting said transmitting circuit to said antenna only when said antenna is used for transmission.
27. In a radio telephone system, an antenna, receiving and transmitting circuits, voice controlled .means for automatically connecting said transmitting circuit to said antennaand means for maintaining said connection only as longas transmissions are made.
2-8. In a radio telephone system, an antenna, receiving and transmitting circuits, voice controlled means for automatically connecting said transmitting circuit to said antenna and means for automatically breaking said connection when transmission ends.
29. In a radio telephone system, an antenna, receiving and transmitting circuits, and voice controlled means to connect said antenna to said transmitting circuit.
30. In a radio telephone system, an antenna normally connected to a receiving circuit, a normally open transmitting circuit, and voice controlled means to automatically open said receiving circuit and close said transmitting circui 31. Ina radio telephone system, an antenna normally connected to a receivmg C11 cuit, a normally open transmitting circuit,
and means controlled by sound waves to automatically open said receiving circuit.
'32. In a radio,telephone system, an an-v tenna normally connected to a receiving circuit, a normally open transmitting circuit, andmeans controlled, by sound Waves to antomatically close said transmitting circuit.
33. In a radio telephone system, a receiving system. a transmitting system and a common antenna therefor, a switch for connecting said antenna to either of said systems, and automatically operated voice controlled means for actuating said switch.
34. In a radio telephone system, a rece ving system, a transmitting system and a common antenna therefor, a switch for connecting said antenna to either of said sys tems, and voice controlled means for automatically operating said switch.
35. In a radio telephone system, a receivlng system, a transmitting system and a common antenna therefor, a sw1tch for connectlng said antenna to either of said systems, and volce controlled means for operating said switch, said means being operated by the closing of avnormally open circuit.
36. In a radio telephone system, a receiving system, a transmitting system and a com- 111011 antenna therefor, a switch for connecting said antenna to either of said systems, and means for operating said switch. said means being controlled by a make and break circuit device and voice controlled means for operating said device.
37. In a radio telephone system, a receiving system, a transmitting system and a common antenna therefor, a switch for connecting said antenna to either of said systems, and means for operating said switch, said means being controlled by a make and break circuit device, operated by sound waves.
In witness whereof, I have hereunto set
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2521860A (en) * 1948-03-30 1950-09-12 Union Switch & Signal Co Emergency break-in system for communication systems
US2935605A (en) * 1955-02-09 1960-05-03 Philips Corp System for the radio-transmission of information
US3132330A (en) * 1961-05-08 1964-05-05 Cie General De Geophysique Electric alarm systems

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2521860A (en) * 1948-03-30 1950-09-12 Union Switch & Signal Co Emergency break-in system for communication systems
US2935605A (en) * 1955-02-09 1960-05-03 Philips Corp System for the radio-transmission of information
US3132330A (en) * 1961-05-08 1964-05-05 Cie General De Geophysique Electric alarm systems

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