US1601109A

US1601109A - Multifrequency resonant network

Info

Publication number: US1601109A
Application number: US548538A
Authority: US
Inventors: Chaffee Emory Leon
Original assignee: Individual
Current assignee: Individual
Priority date: 1922-03-31
Filing date: 1922-03-31
Publication date: 1926-09-28
Anticipated expiration: 1943-09-28

Description

Sept. 28 1926.

E. L. CHAFFEE Filed Mar ch 51, 1922 1Q X Y IIVVENTOR Sept. 28 1926, 1,603,109

E. L. CHAFFEE v MULTI FREQUENGY RESONANT NET WORK Filed March 51. 1922 5 Sheets-Sheet 2 INVENTOR E. L- CHAFFEE MULTIFREQUENCY RESONANT NET WORK- Sept. 28,1926. 1,601,109

Filed March 51. 1922 s Sheets-Sh eet INVENTOR \gaoyiwwy Sept, 28 ,1926. 1 91 39 E. L. CHAFFEE MULTIFREQUENGY RESONANT NET WORK Filed March :51. 1922 5 Sheets-Sheet 4 N N N S r 1 7 R 3 & m,

INVENTOR Sept. 28 1926. 1,601,109

E. L. CHAFFEE MI JLTIFREQUENCY- RESONANT NET WORK Filed March 31, 1922 5 Sheets-Sheet 5 with improved efficiency,

26 and 28.

Patented Sept. 28, 1323.

amass stares r caries.

EMORY LEON CHAIFFEE, OF BELMONT, MASSACHUSETTS, ASSIGNOR TO JOEE HAYS HAMMOND, JR., OF GLOUCESTER, MASSACHUSETTS.

MULTIFREQUENCY BESONANT NETWORK.

Application filed March 31, 1922] Serial No. 548,538.

This invention relates to signaling systems and more particularly to such systems em loying a plurality of frequencies.

enie o'fthe objects of the present inven- 5 'tion are to provide an improved signaling system; to provide improved means for producing simultaneously at least two oscillatory currents of unlike frequencies; to

provide means for producing such currents and for combining currents of unlike frequencies derived from a plurality of sources and amplifying such currents independently; to provide means forreducing interference between parts of a coupled circuit network; and to provide other improvements as will appear from the following description taken in connection with the, accompanying drawings.

- Referring to the drawings:

Figure 1 shows a portion, of a signalling system in which there is produced in a coupled circuit network a plurality of currents of unlike frequencies; Fig. 2 shows a modified form of the system of Figure 1 employing tube generators;

Fig. 3 shows a transmitting station em-- p-loyingthe features of'the invention and forming part ofa radiant energy signalling system;

Fig. 4 shows a modified form of the trans mitting station of Figure 3, using vacuum tube generators, and

Fig. 5 shows another modification in which oscillatory circuits are excited directly by oscillating tubes.

Referring to the drawings and more particularly to Figure 1, one embodiment of'my invention comprlsesa. plurality of sources of alternating current of unlike frequencies, such as alternators 10, 11 each coupled by means of a coil 12, 13 respectively -to a pair of power amplifiers 14, 15. 'Each of these amplifiers consists of a usual, three element vacuum tube having a heatedfilament 17 forming a hot cathode, a grid 18 for controlling the passage of electrons, and a plate 19 upon which the electrons may impinge.

The circuit of the plate 19 of the amplifier 14 includes a pair of inductances 27 and 25. Similarly the circuit of the plate of the amplifier 15 includes a pair of inductances The

inductances

25 and 26 to- -currents produced gether with a third inductance 22coupled thereto, may be consideredv as forming windings of a coupler 20. The inductances 27- and 28 together with'an inductance 23 coupled thereto, may also be considered as forming windings of a coupler 21. The

couplers 20 and 21 have preferably substantially equivalent magnetic and structural characteristics. The windings '22 and 23 are coupled together by means of a coupling which may take any desired form of inductive, capacitative or resistance coupling, that shown being an inductive coupling 24 of cigventional type. I Suitable condensers 29 an 30 and

resistancecoils

31 and 32 are included in the connections to the. coupling 24.

The connections of the windings 25,27, which are in .series, are such as to produce induced currents in the

windings

22, 23 of the couplers 20, 21 having predetermined relative polarities. winding 28 are similar thereto, and roduce with like primary increase or decrease, a secondary current in the winding '23 having the same polarity as in the previous case. The connections of the winding 26 are reversed "with respect thereto so that with a like primary increase or decrease a current of opposite polarity is produced in the winding 22.

The connections of the The circuitc.ompr1sing the winding 22, I

condenser 29, etc. is designated .33, and the circuit comprising the winding 23, condenser 30, etc. is designated 34. The

circuits

33 and 34 are arranged so that their induc tance and capacity constants and the characteristics of the couplin coil 24 cause them to .be resonanflto the 'requencies of both by the alternators 10 and 11. When currents of these selected frequencies co-exist in these coupledfcirc-uits, then for one of these frequencies the currents in both parts are very closely in phase and for the other frequency they are very closely opposite in phase. Thus if for the frequency of the current produced by the source 10 the current in'the circuit 33 is at 35 at its maximum posby the arrow 36 at maximum positive value, at the same moment. For the frequency of current produced by the source 11, however, when the induced current is a maximum positive in circuit 33 as indicated by the arrow 37, it will be substantially a maximum negative in circuit 34, that is, the direction of current will be as indicated by the arrow 38. This property is not confined to networks of the specific form illustrated, but is common to many if not all circuits which have two natural periods of oscillation. sometimes designated two degrees of freedom.

The energy imparted to the coupled

circuits

33 and 34 through the windings 25 and 27 from the amplifier 14, consisting of electric waves of one of the selected frequencies to which the

circuit networks

33 and 34 are resonant, is transmitted thereto freely. Let it be assumed that at a given moment the currents are flowing in the direction indicated by the

arrows

35, 36. The couplings provided to the amplifier 15 by the windings 26, 28 are so connected, however, that waves of the frequency delivered from the amplifier 14 do not appear in the plate circuit of the amplifier 15, the windings 26, 28 being connected so that these currents op ose each other.

n the other hand, the energy imparted to the coupled

circuits

33 and 34 through the windings 26 and 28 from the amplifier 15, consisting of electric waves of one of the selected frequencies to which these circuits are resonant, is transmitted thereto freely. The direction of the currents of this different frequency is as indicated by the arrows 37, 38 respectively, and since the connections of the windings 25, 27 are as previously described, the effects of these Waves in the plate circuit of the amplifier 14 are substantially neutralized.

Thus it will be seen that substantially no interaction between the sources is produced, and that the respective power amplifiers operate independently of each other, so that neither is subjected to currents of any frequenc other than that which it is intended shall fie amplified by it. This condition of having only a single frequency to amplify is the condition under which a high efiiciency, that is a high ratio of output energy to input energy, is obtained, with amplify lng devices of this character, and this constitutes an important feature of my invention. Accordingly amplifier tubes 14. 15 of relatively great power can be employed efficiently.

Referring to Figure 2 there is provided the

same circuit network

33, 34 as in the previous case, the current supply to the inductive couplings 12 and 13 being obtained from a corresponding number of vacuum tube generators, such as 50, 51. Each of these includes a three-element vacuum tube, such as 52, of conventional type, and a couplin 53 whereby the plate circuit is coupled back to the grid circuit and regenerative oscillations are obtained continuously.

The operation of the system of Figure 2 is similar to that described for Figure 1, with the exception that

sources

50, 51 provide the energy used.

Referring to Figure 3, a transmitting station comprising the features of the invention includes a transmitting antenna- 101 connected 'to earth 102 through the circuit 34 of the coupled

network

33, 34, corresponding to the coupled

network

33, 34 of Figure 1. A pair of sources of alternating current of unlike frequencies, such as alternators 110, 111 are inductively coupled by means of a pair of couplers 112, 113, respectively, to a pair of power amplifiers 114. 115. The circuit 116 and its operations is substantially the same as that of network 16 of Figure 1, like parts being designated by numerals having corresponding tens and units digits.

Thus in a manner similar to that described in detail for Figure 1, energy is transmitted to the coupled

network

33, 34 from a plurality of sources of alternating currents of unlike frequencies independently, and each of these currents may be amplified by means of amplifiers of relatively high power, and at a great efficiency.

Referring in detail to Figure 4. this shows a transmitting station corresponding to the transmitting station of Figure 3, excepting that in place of the alternators 110, 111 there is provided a plurality of sources of current, such as 150, 151 each including an oscillating vacuum tube 152. These are the same as in Figure 2, like parts being designated by reference characters having like tens and units numerals. The arrangement is such that the oscillator 151 produces a frequenc different from that produced by the osci lator 150.

It is obvious that the transmitting stations of Figures 3 and 4 may be employed as parts of systems for communication through the ether. Messages may be transmitted in any suitable manner. as for example, by interrupting one of more of the sources of current.

The modified embodiment of the invention shown in Figure 5 comprises a

circuit network

33, 34 as in Figure 2, the oscillatory circuits of the network being excited directly by a pair of vacuum tubes 60 and 61. A coupling 62 is provided for inductively coupling the plate and grid circuits of the tube 60 to each other and to the inductances 25 and 27. Thus the tube 60 is connected for feeding back energy from its output to its input circuit, and the regenerative oscillations thereby produced are impressed upon the

circuit network

33, 34 in the same mannor as was described previously in connection with Figures "1 and 2. Similarly, a coupling 63 is provided for inductively coupling the plate and grid circuits of the tube 61 to each other and to inductances 26 and 28. The regenerative oscillations thus produced are impressed upon the.

circuit network

33, 34 in the samemanner as described in connection with the corresponding inductances 26 and 28 of Figure 1.

Suitable means suchas a tuning condenser 64 may be provided for determining the frequency of current produced by the tube 60 and its' associated couplings; and a similar means such as a condenser 65 is pro-- vided for the tube 61 and its associated couplings. The condenser 65 is adjusted to a different value from that of the condenser 64, so that currents of relatively different frequencies are produced.

The operation of the system of Figure 5, will be obvious from'the foregoing description taken in connectin with the description of the operation of Figure 2. It will be seen "that. oscillatory currents of unlike frequencies are produced, and these are independently impressed upon the

network

33, 34, and allowed to coexist therein, their values being coincident respectively with the two natural frequencies of the coupled

network

33, 34.

Thus it will be seen that I have provided a simple and economical means for independently generating two currents and applying them to a single network without having either current affect the generation of theother current. By this means substantially no reaction on either source of current exists due to the generation of current by the other source. 7

Furthermore, two sources of alternating currents of different frequencies may readily and efliciently be held-at constant difference, that is, although their periodicities may vary slightly due to unavoidable variations in the operation of the sources, the difference may be held substantially constant.

It is to be noted that in the embodiments of Figures 3 and 4, the amplitude of the combined currents of different frequencies is at a minimum in circuit 33 when it is at a maximum in circuit 34 and vice versa. Accordingly the point of energy. dissipation is shifted from one portion (33) of the coupled network to the other portion (34) alternately, the action of the energy sources remaining substantially constant.

The construction illustrated sider to be the preferred embodiment ofmy invention and it is therefore to be distinctly understood that I do not limit'myself there: to as many changes may be made in point of detail and other embodiments, resorted and described herein is merely what I now con so 'tro-motive forcesof substantially equal value and opposing one another.

2. A system for the. production of oscillatory energy comprising a-circuit network, means co nprising a regenerative vacuum tube for impressing upon said network at a pair ofv spaced portions thereof a pair of substantially synchronous, oscillating,

electro-motive forces of substantially equal value and mutually aiding, and means comprising a' regenerative vacuum tube for impressing-upon said network at a pair of spaced portions thereof and in opposite relations a second pair of substantially synchronous, oscillating, electro-n'iotive I forces of substantially equal value and of a frequency different from that of the first-mentioned electro-motive forces.

3. A system for the production of oscillatory energy comprising a circuit network, a three-electrode, electron emitting device, means for coupling the output circuit of said device to said network at'a pain of spaced portions thereof in a' manner to impress thereon a pair of substantially synchronous, oscillating, GlGCtIO-lIlOtlVG forces a of substantially equal value and, mutually aiding, a second three-electrode, electron emitting device, and means for coupling the output circuit of said second device to said network at a pair of in a manner to impress thereon a second pair of oscillating, electro-motive forces of substantially equal value and opposing one another.

latory energy comprising a circuit network,

means comprising an electron emitting device connected for continuous regeneration and an amplifier for amplifying the currents produced by said regeneration for 1mof spaced portions there'- 4. A system for the production of oscilpressing upon said network at a pair of spaced portions thereof a pair of substantially synchronous, oscillating, electro-motive forces of substantially equal value and mutually aiding, and means comprising an electron emitting device connected for continuous regeneration and an amplifier for amplyfying the currents. produced by saidregeneration for impressing upon said neti work at a pair of spaced portions thereof a second pair of oscillating electro-motive forces of substantially equal value and opposing one another.

5. A system for the production of oscil latory energy comprising a circuit network including two, inter-coupled circuits each having inductance and capacity, means comprising a three-electrode, electron emitting device and like couplings between the output circuit of said device and the network for impressing upon said network at a-pair of spaced portions thereof a pair of substantially synchronous, oscillating. electromotive forces of substantially equal Value and mutually aiding, and means comprising a second, three-electrode electron emitting device and reversely-arranged couplings between the output circuit of said second device and the network for impressing upon said network at a pair of spaced portions thereof and in opposite phase relations a second pair, of oscillating electro-motive forces of substantially equal value and of a frequency different from that of the firstmentioned electro-motive forces.

6. A system for the production of oscillatory energy comprising a circuit network, means comprising an electron emitting device connected for producing oscillations of a predetermined frequency and a second electron emitting device for amplifying the currents produced by said device for impressing upon said network at a pair of spaced portions thereof a pair of substantially synchronous oscillating electro-motive forces of substantially equal value and mutually aiding, and means comprising a third electron emitting device connected-for continuously producing oscillations of a relatively different frequency, and an additional electron emitting device for amplifying the currents produced by said third named electron device for impressing upon said network at a pair of spaced portions thereof a second pair of oscillating electro-motive forces of substantially equal value and opposing one another.

7 Apparatus for producing oscillating current comprising a plurality of couplers each having a plurality of windings, a source of oscillating current of a predetermined frequency, an amplifier for amplifying said current, said source and amplifier being operatively connected to a winding of each of the couplers, a second source of oscillating current of relatively different frequency. a second amplifier for amplifying said second current, said second source and second amplifier being operatively connected to a second winding of each of the couplers, and a network composed of inter-coupled circuits and including a third winding of each of the couplers, the connections of at least one of the windings of one of the couplers being unlike the connections of the corresponding winding of the other coupler. Y

8. Apparatus for producing oscillating current comprising a plurality of couplers each having a plurality of windings, a source of periodic impulses of a predetermined frequency, an amplifier for amplifying said impulses, said source and amplifier being operatively connected to a winding of each of the couplers, a second source of periodic impulses of relatively different frequency, a second amplifier for amplifying said second named series of impulses, said second source and second amplifier being operatively connected to a second winding of each of the couplers. a network composed of two. inter-coupled circuits and including a third winding of each of the couplers, the connections of one of the first named windings of one of said couplers being reverse with respect to the connections of the corresponding winding in the other coupler.

9. A system for transmitting radiant energy comprising a circuit network resonant to currents of two frequencies and including two, inter-coupled circuits each having inductance and capacity, means for impressing upon the network at two portions thereof spaced apart substantially synchronous,

alternating, electro-motivc forces of one of said frequencies, the instantaneous values of the currents produced in the respective portions of the network by said electro-motive force being substantially equal and of like. phase, and means for impressing upon the network at two spaced portions thereof additional substantially synchronous, alternating, electro-motive forces of the other of said frequencies, the instantaneous values of the currents produced in the respective portions of the network by said second named electro-motive forces being substantially equal and opposing.

10. A system -for transmitting radiant energy comprising a circuit network resonant to currents of two frequencies. meansincluding a three-electrode vacuum tube for impressing upon the network at two portions thereof spaced apart periodically varying electro-motive forces, the instantaneous values of the currents produced'in the respective portions of the network by said electro motive forces being substantially equal and aiding, and means including a three-electrode vacuum tube for impressing upon the network at two spaced portions additional periodically varying electro-motive forces having a relatively different frequency, the instantaneous values of the currents produced in the respective portions of the network by said second named electro-motive force being substantially equal and opposing.

11. A system for producing oscillatory energy comprising a plurality of sources of frequencies, and means for impressing said impulses upon the, network, including couplings reversely arranged to prevent current impulses of one of saidfrequencies from reacting on the source of impulses of theother of said frequencies.

- 13. A- system for transmitting radiant energy comprising a plurality of sources of periodic impulses of unlike frequencies, a circuit network resonant to a plurality of frequencies and means for impressing said impulses upon the network comprising reversely arranged inductive couplings preventing current impulses of one of said frer quencies from reacting through the network upon a source of impulses of another of said frequencies, 1 a

14, A system for transmitting radiant energy comprising two sources of periodic impulses of unlike frequencies, a circuit nettov both of said frequencies and including two inter-coupled circuits each having inductance and capacity, means for impressing said impulses upon the network comprisingreversely arranged couplings for preventing current impulses of one of said frequencies from reactingupon the source of impulses of the other of said frequencies, and means operatively connected with the network for impressing energy upon the ether.

15. A system for transmitting radiant energy comprising a pair ofsources ofalternating currents of unlike frequencies, a circuit network comprising a pair of coupled oscillatory circuits, and reversely arranged couplings for impressing said currents upon thenetwork soas to substantially neutralize work resonant the tendency 'for one of said currents to react through the net work on the source of current of different frequency.

- 16. A system for producing oscillatory currents for systems of communication comprising a circuit network including two, inter-coupled circuits each having inductance 1 and capacity, means for impressing upon said network "at difierent portions thereof two substantially synchronous oscillating electro-motive forces of substantially equal value, andmeans for impressing upon said network at two other different portions thereof a secondpair of oscillating electromotive forces of substantially equal value,

the phaserelationshipbetween said pairs of electromotive forces being such that energy is impressed alternately upon the two different portions of the net work.

17. A system for the production of oscillatory energy comprising a circuit network including two inter-coupled circuits each having inductance and capacity, means for impressing upon said network at two spaced portions thereof substantially synchronous, oscillating, electro-motive forces of substantially equal value and like phase, and means for impressing upon said network at two spaced portions thereof and in opposite phase relations two substantially synchronous, osv cillating, electro-motive forces of substantially equal value and of a frequency different from that of the first-mentioned electro-motive forces. A

18. A system for the production of oscillatory energycomprising a circuit network including two inter-coupled circuits each having inductance and capacity and one of said circuits containing an antenna and ground, means for impressing uponsaid network at two spaced portions thereof substantially synchronous oscillating electro-mot'ive forces of substantially equal value and like phase, and means for impressing upon said network at two spaced portions thereof and in opposite phase relations two substantially synchronous oscillating electro-motive forces of substantially equal value and of a frequency diiferentfrom that of the first-mentioned electro-motive forces.

19. A system for-the production of oscillatory energy comprising a circuit network including two circuits inductively coupled together and each containing inductance and capacity, means for impressing upon said network at two spaced portions thereof substantially synchronous oscillating electromotive forces ofsubstantially equal value and like phase, and means for impressing upon said network at two spaced portions thereof and in opposite phase relations two and of a frequency different from thatof the first-mentioned electro-motive forces.-

20. A system for the-production of oscillatory energy comprising a circuit network including two inter-coupled circuits each having inductance and capacity, means for impressing upon saidnetwork at two spaced portions thereof substantially synchronous oscillating electro-motive forces of substanti ally equal value and like phase, means for impressing upon said network at two spaced portions thereof and in opposite phase relations two substantially synchronous oscillating electro-motive forces of substantially equal value and of a frequency different from that of the first-mentioned electro-motive forces, and means connectedwith said network .for radiating energy into the ether.

21. A system for the production of oscillatory energy comprising a plurality of sources of electro-motive force of different frequencies respectively, a circuit network resonant to currents of a plurality of said frequencies and comprising two, inter-coupled circuits each having inductance and, capacity and one containing an antenna and ground, means for impressing upon said network at two spaced portions thereof and from one of said sources substantially synchronous, oscillating, electro-motive forces of substantially equal value and like phase, and means for impressing upon said network at two spaced phase relations two substantially synchronous, oscillating electro-motive forces from another of said sources and of substantially equal value.

portions thereof and in opposite 7 22. A system for the production of oscillatory energy comprising two sources of electro-motive force of two different frequencies respectively, a circuit network resonant to currents of said two frequencies and comprising two inter-coupled circuits, means for impressing upon said network at two spaced portions thereof and from one of said sources substantially synchronous, oscillating, electro-motive forces of substantially equal value and like phase, and means for impressing upon said network at two spaced portions thereof and in opposite phase relationtwo, substantially synchronous, oscillating, electro-motive forces from another of said sources and of substantially equal value.

Intestimony whereof I hereunto afiix my signature.

, EMORY LEON CHAFFEE.