US1563342A - Signaling system - Google Patents
Signaling system Download PDFInfo
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- US1563342A US1563342A US548679A US54867922A US1563342A US 1563342 A US1563342 A US 1563342A US 548679 A US548679 A US 548679A US 54867922 A US54867922 A US 54867922A US 1563342 A US1563342 A US 1563342A
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- 230000011664 signaling Effects 0.000 title description 6
- 239000004020 conductor Substances 0.000 description 29
- 238000004804 winding Methods 0.000 description 29
- 230000010355 oscillation Effects 0.000 description 12
- 230000008878 coupling Effects 0.000 description 10
- 238000010168 coupling process Methods 0.000 description 10
- 238000005859 coupling reaction Methods 0.000 description 10
- 230000000694 effects Effects 0.000 description 8
- 230000001939 inductive effect Effects 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 4
- 230000003247 decreasing effect Effects 0.000 description 3
- 230000003534 oscillatory effect Effects 0.000 description 3
- 230000005284 excitation Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 1
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03C—MODULATION
- H03C5/00—Amplitude modulation and angle modulation produced simultaneously or at will by the same modulating signal
Description
Dec. 1, 1925 1,563,342
F. CONRAD S IGNALI NG SYSTEM Filed A ril 1922 2 Sheets-Sheet 1 mlmm v 41%? I I 72 A? 2 INVENTOR Fw /r fol/rad.
: ATTORNEY Patented Dec. 1, 1925.
1,563,342 UNITED STATES PATENT OFFICE..
FRANK CONRAD, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY. A CORPORATION OF PENNSYLVANIA.
SIGNALING SYSTEM.
Application filed i e 1, 1922. Serial No. 548,679.
7'0 071 whom 'ifimaq concern:
Be it known that I, FRANK CONRAD, a citizen of the United States, and a resident of Pittsburgh. in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Signaling Systems, of which the following is a specification.
My invention relates to wireless transmission systems and more especially to oscillation generators adapted to be excited by alternating-current sources of energy.
One object of my invention is to provide an oscillation-generator system employing vacuum tubes as oscillation generators which admits of excitation directly by alternating currents of commercial frequency.
Another object of my invention is to so embody a sustaining inductance in the alternating-current supply system for the oscillator tubes as to maintain a substantially constant power supply to the oscillator tubes.
Inasmuch as it would require a sustaining inductance of infinite value in the alternating-current mains to completely smooth out the fluctuations in the power supply to the oscillator tubes, it is apparent that a residual fluctuation will remain.
A further object of my invention, therefore, is to eliminate the residual fluctuations just mentioned, thereby adapting my system for wireless telephony.
A still further object of my invention is to .provide means whereby the generator system. may be rendered oscillatory or nonoscillatory, at will, and, at the same. time, provide means for limiting the supply currents of the tubes to safe values, thereby adapting my system for the transmission of wireless telegraph signals.
Other objects of my invention will appear more fully from the following description of the nature, mode of operation and various applications of my invention.
Heretofore, when employing alternatingcurrent power for the excitation of oscillator-tube systems, it has been customary to employ a separate set of rectifier tubes. Such tubes are expensive and require care and attention, which is undesirable.
I find, however, that, by employing a system as hereinafter described, the rectitier tubes may be eliminated and the system may be energized directly from the alterdesired result may be obtained by simultaneously controlling, at will, the amount of grid-leak in the oscillatory circuit and the impedance of the alternating-current supplv circuit.
lVith these and other objects and applications in View, my invention further consists in the mode of operation and the constructional details hereinafter described and claimed and illustrated in the accompanying drawing, wherein:
Figure 1 is a diagrammaticview of a simplified wireless telephone system embodying I my invention Fig. 2 is a similar view showing means for balancing'out the residual power fluctuations obtaining in the previous system;
Fig. 3 is a similar view, but showing still another means for removing the disturbing. effects of the residual power fluctuations;
' Fig. 4 is a View similar to that of Fig. l, but showing my system so modified as to admit of the transmission of wireless telegraph signals.
In Fig. 1, a pair of thermionic tubes 1 and 2. which are caused to serve both as oscillation generators and as rectifiers, are shown as comprising anodes 3 and 4, gridmembers 5 and G and hot cathodes 7 and 8, respectively, the latter being energized from a common source of direct-current energy 9. The tubes 1 and 2 may be successively energized by alternate half cycles of an alternatingcurrent source of energy 11 of commercial frequency through a transformer 12. The anodes'3 and 4 are connected to opposite terminals of a pair of series-connected secondary windings 13 and 14-. of the transformer '12 by conductors, 15 and 16, respectively. The hot cathodes 7 and 8 are connected to the common terminal17 of the'secondary windings 13 and 14 by a'conductor 18. Thep'rimary transformer windings 19 and 21 are serially connected to the source of energy 11 by conductors 22 and 23, re-
spectively.
Inasmuch as the distributed capacity of the transformer windings 13 and 14 may be of suflicient value to cause the dissipation of a considerable amount of radio-frequency energy therein, I have found it desirable to connect radio- frequency choke coils 24 and 25 in the anode leads 15 and 16, respectively.
The transformer 12 is so designed as to provide, for each anode conductor, a sustaining inductance of suflicient value to maintain the current in one conductor while that in the other conductor is building up to approximately its full value, that is to say, to so prolong the currents in each conductor that their sum is practically a constant quality at all times. One type of transformer for carrying the above desired result into effect is shown in my United States Patent No. 931,114, filed January 10, 1908,
' and assigned to the Westinghouse Electric & Manufacturing Company, and hence a detailed description thereof is unnecessary.
The oscillation generator' system comprises the usual plate-filament and gridfilament circuit (onnections. The anodes 3 and 4 are connected to an adjustable tappoint 26 of an inductance coil 27 through condensers 28 and 29, respectively. The condensers are provided in order to prevent the short-circuiting of the low-frequency currents. The filaments 7 and 8 are connected, by a conductor 31, to an adjustable tap-point 32 of the tuning inductance coil 27. A conductor 33 serves to connect this point to ground.
In operation, the tubes 1 and 2 alternately serve as oscillation generators with successive alternations inthe polarity of the potentials impressed upon the anode elements 3 and 4 thereof. Hence, it can be seen that both half cycles of the alternating currents lmpressed upon the system are employed for the generation of high-frequency currents. The effect of the sustaining induc-' tances, which are embodied in the transformer windings 13 and 1-4,, is to prolong the power supply to one tube while that of the other tube is increasing to its maximum '58 of the transformer potential variations in the secondary windvalue, thereby removing, to a great extent, the residual power fluctuations.
-Modulation of the radio-frequency currents generated by the oscillator tubes 3 and 4 is effected in a manner well known in'the art upon speaking into the microphone transmitter 43. As hereinbefore stated, a
residual fluctuation in the radio-frequency wave of power frequency will remain, inasmuch as to obtain a perfectly uniform highfrequency wave would necessitate the use" comprising anodes 47 and 48, grids 49 and 51 and filaments 52 and 53, respectively, in shunt relation to secondary windings 13 and 14, anodes 47 and 48 being connected to conductors 15 and 16, respectively.
The filaments 52 and 53 are connected in parallel with the filaments 7 and 8 of the oscillator tubes and energized from the common source of energy 9. The conductor 18, which serves to connect the several filaments to the common terminal 17 of the transformer secondary windings, may include a primary winding 58 of a transformer 59. The grid elements 49 and 51 are connected, by a common conductor 61, to the several filaments. The conductor 61 may include a biasing source of energy 62, a secondary winding 63 of a modulating transformer 64 and a primary winding 65 of the transformer 59, a resistor 66 being connected in shunt relation to said primary winding 65 for a purpose hereinafter described. A primary winding 67 of the modulating transformer 64 is included in a circuit which may contain, in addition, a direct-current source of energy 68 and a microphone transmitter 69.
This system is further distinguished from that of Fig. 1 in the means for supplying the sustaining inductance to the oscillator tube leads. Instead of relying entirelyv upon the transformer to supply the sustaining inductance, a special sustaining reactor 71 is provided comprising a magnetizable core member 72 and a pair of magnetizing windings 73 and 74, the latter being serially included in the anode leads 15 and 16, respectively.
The residual fluctuations of power he quency which traverse the primary winding 59 are translated into ing 65 thereof and impressed upon the grid elements 49 and 51. The effect of such grid-potential variations is to produce such is equally effective when connected in s ant to the secondary winding 58 thereof.
Vthen voice waves enter the microphone transmitter (59, the potentials of the grids 4!) and 51 are modulated in accordance with the varying intensity of the sound Waves.
During a one-half-cycle of the impressedelectromotive force, when the] tube 1 is functioning as an oscillator, the modulator tube 45 is effective. whereas. during the next half-cycle, when the tube 2 is functioning as an oscillator, the modulator tube 46 becomes effective. The operation and circuit arrangement of this system are otherwise as indicated forthose of Fig. 1.
Referring to Fig. 3, the arrangement therein shown differ from that of Fig. 2 in the means for balancing out the residual power fluctuation. An additional pair of amplifier tubes and 76 are herein employed for amplifying the effects of the Imicrophone transmitter 69, as hereinafter described. The additional amplifier tubes 75 and 76 comprise anodes 77 and 78, grid electrodes 79 and 81, and hot cathodes 82 and 83, respectively, the latter being energized from a common source of direct-current energy 84.
The tubes are energized by means of a transformer 85 having transformer connections similar to the transformer 12. Anodes 77 and 7 ,8 are connected, by conductors 86 and 87 to opposite terminals of the seriesconnected secondary windings. 88 and 89 of the transformer 85. The hot cathodes 82 and 83 are connected to the common transformer secondary terminal by means of a comluetor 91. The primary windings 92 and 93 of the transformer 85 are serially connected, by conductors 94 and 95, tothe source of alternating-c1lrrent energy 11. The grid elements 7 9 and 81 are connected, by a common conductor, to the hotcathode elements 82 and 83, through 'a secondary winding 97 of a modulating transformer 98, the primary winding 99 of which is serially included in a circuit containing, in addition, a source 100 of directcurrent energy and the microphone transmitter 69.
The anodes 77 and 78 of the amplifier tubes 75 and 78 are connected, by conductors 101 and 102, to the grid elements 49 and 51 of the modulator tubes 45'and 46, through stopping condensers 103 and 104, respectively. The hot-cathode elements .82 and 83 of the am lifiertubes 75 and 76 are connected to the aments 52 and 53,013 the moduletor tubes 45 and 46 and to ground by means of a ground conductor 10:"). The grid elements 49 and 51-of the modulator tubes 45 and 46 may be given a negative bias by means of conductors 106 and 107 which extend from said grid elements to the hotcathode elements 52 and and which ini clude a common direct-current source of energy 108 and individual radio-frequency choke coils 109 and 110, respectively.
In the system shown in Fig.8, the lowfrequency fluctuations of power in the amplifier tubes 7 5 and 76 may be decreased by decreasing the sustaining'inductances of the transformer 85, the adjustment being such that the main power-frequency fluctuations obtaining in the oscillator tubes 1 and 2 will be eliminated;
en voice-waves enter the microphone, transmitter 69, the power supplied to the oscillator tubes 1 and 2 is modulated during successive half-cycles of the impressed elec tromotive force, thereby causing the resultant high-frequency currents in the antenna system to be correspondingly modulated, all as will be understood by those versed in the art. The operation and circuit arrangements of this system are otherwise as indicated for that of Fig. 2.
The arrangement shown in Fig. 4 distin-' vguishes from that of Figrl in that means have been provided, whereby the system may be employed for the transmission of wireless telegraph signals In the several arrangements shown, the effect of the sustaining inductance of the transformer 12 supplying the oscillator tubes, or of the. reactor 71 is such as to prevent sudden interruptions of the alternating-supply currents. Hence, certain switching systems of telegraphy, involving the opening of either the high-frequency or the low-frequency circuits to form the necessary dots and dashes, are ineffective.
In the arrangement shown in Fig. 4, to form the dots and dashes, I simultaneously short-circuit a resistor 112, which is normal-o 1y included in circuit with the primary 'member 116 of a normally closed relay 117.
y A normally open relay 118 is connected in shunt relation to the resist-or 112 by conductors 119 and 121.
The resistor 112, which may be any form of im edance device, is of such impedance that t 9 current supplied to the oscillator tubes land 2-is suitably reduced durin the non-signaling periods. Actuating win ings 122 and 123 of the relays 117- and 118 are connected in scries-cirialit relation by a conductor 121 and ground. The conductor 121 may include a source of energy 125 and a controlling key 126.
In operation, when the key 126 is closed, the relays 117 and 118 are simultaneously energized to effect the short-circuiting of the resistor 112 and the open-circuiting of the grid-condenser shunt pathlli i. r, The system now oscillates in a. well known manner. lVhen the key 126 is opened, the relays 117 and 118 are deenergized, with the result that the grid condenser 36 is short-circuited and the resistor 117 rendered effective to limit the current supplied to the oscillator tubes 1 and 2. The system is now in a non-oscillatory state. As can readily be seen, the telegraph signaling system embodied in Fig. 1 may be readily applied to any of the foregoing wireless telephone systems-1.;-
Asa further modification, I have included,
in the shunt path 113, a source of ener '127, the effect of which is to decrease t e impedance of the plate circuits of the oscillator tubes and hence decrease the power loss therein when the system is rendered nonoscillatory. I v I Inasmuch as the fluctuations in the supply circuits may consist of harmonics-20f .power frequency, the balancing of the power fluctuations may be made more complete by including, in the supply circuit to theoscillator tubes 1 and 2, inductance'devioes tuned to particular harmonics. For the purpose of illustration, I have shown one such inductance device 128 in the filament return circuit 18 as shunted by a variable condenser 129 whereby the inductance device 128 may be tuned to the frequency of the harmonic which it is desired to eliminate.
While I have shown several embodiments of my invention, for the purpose of describing the same and illustrating its several applications, it is apparent that various changes and modifications may be made therein without departing from the spirit of my invention and I desire, therefore, that only suchlimitations shall be imposed thereon as are indicated in the prior art or are specifically set forth in the appended claims.
I claim as my invention:
1. Ina radio signaling device, an electrontube oscillator, a source of periodic current supplying said oscillator, and meanswhereby the current supplied to said oscillator ismaintained substantially constant, said means including a transformer having large inductive reactance.
2. In a radio signaling device, an electron-tube modulating device, an electrontube oscillating device, a source of periodic current supplying said devices and means whereby fluctuations caused by the peri'-.
electron tubes having plate, grid and filament elements, supply conductors connecting said plates to opposite terminals of said secondary windings, and a common supply conductor connecting said filament elements to an intermediate point in said secondary winding, said secondary winding being so designed as to have a large inductive reactance, whereby the sum of the currents in said supply conductors is practically a constant quantity at all times.
4. ,An electrical system comprising a source of alternating currents, a transformer} having-primary and secondary windingsflconductors associating said primary winding with said source, a pair of oscillator tubes having plate, grid and filament elements, supply conductors connecting said plates to opposite terminals of said secondary winding, 2. common supply conductor connecting said filament elements to an intermediate point in said secondary winding, said secondary winding being so designed as to have a large inductive reactance,
-whereby the sum of the currents in said plate conductorsis practically a constant quantity at all times, and means associated with said tubes for causing the same to function as oscillation generators.
5. An electrical system comprising an alternating-current source of power, a air of oscillator tubes, means for so coup ing said oscillator tubes to said source of power that both half-waves of the impressed electromotive forces may be employed, the resulting radio-frequency oscillations being modulated in accordance with the frequency of said source of power, inductive reactance means for reducing fluctuations in the supply to said tubes, whereby said modulation may be decreased, and means for balancing out the remaining part of said modulation.
6. An electrical system comprising an alternating-current source of power, a air of oscillator tubes, means for so coup ing said oscillator tubes to said source of power that both half-waves of the impressed electromotiv'e forces may be utilized, the resulting radio-frequency oscillations generated by said oscillator tubes being modulated in accordance with the frequency of said source, inductive reactance means for reducing fluctuations in'the power-supply to said tubes, whereby said modulation troducing, in
means is practically eliminated, and means for insaid power-supply, a modulation comparable to .the resldual modulation and in phase-opposition thereto.
7 An electrical system comprising an alternatinga-urrent source ofpower, a pair of oscillator tubes. means for so coupling said oscillator tubes to said source of power that both half-waves of the 1m: pressed electromotive forces may be utilized, the resulting radio-frequency oscillations generated by said oscillator tubes being modulated in accordance with the frequency of said source of power, induct ve reactance means embodied in said coupling means and operating to reduce fluctuations in the power supplied to said tubes,'whereby said modulation is practically eliminated, a pair of modulator tubes parallelly associated with said oscillator tubes. and means for so modulating the impedance of said modulator tubes as to oppose the residualpart of modulation.
S. An electrical system comprising an alternating-cnrrent source of power, a pair of oscillator tubes, means for so coupling said oscillator tubes to said source of power that both half-waves of the impressed electromotive forces may be utilized, the resulting radio-frequency oscillations generated by said oscillator tubes being modulated in accordance with the frequency of said source of power, 1nduct1ve reactance for reducing fluctuations in the power supplied to said tubes, whereby said modulation is practically eliminated, a pair of modulator tubes parallelly associated with said oscillator tubes, means for modulating the .impedances of said modulator tubes in accordance with the modulation but in phase-opposition thereto, and means for further modulating the impedances of said modulator tubes in accordance with a signal. a
9. A system for producing oscillations comprising an alternating-currentsource of power, oscillator tubes connectedthereto, means for reducing fluctuations in the power supplied to said oscillator tubes, a slight residual fluctuation remaining, amplifier tubes connected to said source, means for reducing fluctuations in the power supplied to said amplifier tubes, a slight residual fluctuation remaining, and means for so associating the oscillator and the amplifier tubes as to balance the residual fluctuations of the amplifier tubes against the residual fluctuations of the oscillator tubes.
10. A system for producing oscillations comprising an alternating-current source of power, oscillator tubes connected thereto,
means for reducing fluctuations in the power supplied to said oscillator tubes, a
slight residual fluctuation remaining, am-
plifier tubes, a transformer, connections for 1 pressed electromotive forces, means associated with said connections for reducing fluctuations m the power supplied to said amplifier tubes, a slight residual fluctuas tion, and means for so associating said amplifier tubes and said oscillator tubes as to balance the residual fluctuation in the amplifier circuits against that in the oscillator circuits. I c 11. In an electrical system, an alternating current source of power, oscillator tubes, a transformer for so coupling said source and said tubes as to admit of the utilization of both half-waves of the impressed elect-romotive forces, means tending to substantially remove fluctuations in the mwer-supply to said tubes, amplifier tubes, a transformer so coupling said amplifier tubes and said source as to-admit of the utilization of both half-waves of the impressed eleetromotive forces, means tending to substantially remove fluctuations in the power supplyto said amplifier tubes and means so associating the oscillator and the amplifier tubes as to balance the amplifiertube residual fluctuations against the oscillator-tube residual fluctuations.
12. In an electrical system, an alternating-current source of power, oscillator tubes, a transformer so coupling said source and said tubes as to admit of the utilization of both half waves of the impressed electro-.
motive forces, inductive reactance means embodied in said transformer for substantially removing fluctuations in the power supplied to sa tubes, amplifier tubes, a transformer so coupling said amplifier tubes fier tubes, and means so associating the oscillator and the amplifier tubes as to balance the amplifier-tube residual against the oscillator-tube residual fluctuations.
,13. In an electrical system, an alternating-current power supply, oscillator tubes, a transformer so coupling said power in said last-mentioned transfluctuations supply and said tubes as to admit of the utilization of both half-waves of the impressed electromotive forces, means tending to substantially remove fluctuations in the power supply to said tubes, amplifier tubes, 1,25
a transformer 'so coupling said amplifier tubes and said power supply as to admit of the utilization of both half waves of the impressed electromotive forces, means tending to substantially remove fluctuations in the power supply to said am lifier tubes and means associating said amp ifier tubes with the control elements of said modulator tubes, whereby the amplifier residual fluc tuations may be caused to balance the oscillator residual fluetuation.
14. In an electrical system, an alternatingcurrent power supply, a pair of oscillator tubes, a modulator tube having a controlling electrode parallelly associated with each oscillator tube, a transformer so coupling said power supply and said tube as to admit of the utilization of both half waves of the impressed electromotive forces, a sustaining inductance embodied in said transformer winding tending to substantially eliminate fluctuations in the power supply to said tubes, amplifier tubes having control electrodes, means for supplying said amplifier tubes from said power supply with currents having residual fluctuations similar to those in said oscillator-tube circuits, circuit con-' nections for impressing said amplifier fluctuations upon said modulator control electrodes, whereby the residual fluctuations in said oscillator circuits may be eliminated, and means carrying modulating currents associated with said amplifier control electrodes.
In testimony whereof, I have hereunto subscribed my name this 23rd day of March, 1922.
FRANK CONRAD.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US548679A US1563342A (en) | 1922-04-01 | 1922-04-01 | Signaling system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US548679A US1563342A (en) | 1922-04-01 | 1922-04-01 | Signaling system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US1563342A true US1563342A (en) | 1925-12-01 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US548679A Expired - Lifetime US1563342A (en) | 1922-04-01 | 1922-04-01 | Signaling system |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US1563342A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2571816A (en) * | 1949-09-09 | 1951-10-16 | Westinghouse Electric Corp | Tetrode keying system |
| US2577512A (en) * | 1945-03-22 | 1951-12-04 | Harold S G Cooper | Communication system |
| US3614668A (en) * | 1969-02-20 | 1971-10-19 | Nippon Electric Co | Double-balanced modulators of the current switching type |
-
1922
- 1922-04-01 US US548679A patent/US1563342A/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2577512A (en) * | 1945-03-22 | 1951-12-04 | Harold S G Cooper | Communication system |
| US2571816A (en) * | 1949-09-09 | 1951-10-16 | Westinghouse Electric Corp | Tetrode keying system |
| US3614668A (en) * | 1969-02-20 | 1971-10-19 | Nippon Electric Co | Double-balanced modulators of the current switching type |
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