US1670893A - Electrical system - Google Patents

Description

May 22, 1928.

S. P. LEVENBERG ELECTRICAL SYSTEM Filed Dec. 8, 1923 2 Sheets-Sheet 1 all" ATTORNEY May 22, 1928.

S. P. LEVENBERG ELECTRICAL SYSTEI Filed D60. 1923 2 Sheets-Sheet 2 lNvENl 'p 7 2 p BY ATTORNEY Patented May 22, 1928- .um'rso STATES PATENT OFFICE.

SAMUEL P. LEVENBERG, 01' NEW YORK. N. Y., ABBIGNOB TO rm: nvmm con- POBATION, 0]? NEW YORK, N. Y.,

A CORPORATION 0] m YORK.

ELECTRICAL SYSTEM.

Application men December s,'1a2a. Serial m. mass.

This invention relates to electrical circuits and with regard to its more specific features to a circuit for the reception of electrical waves of radio frequency.

An object of this invention is to provide a system of the character described in WhlCh the power supplied for the system may taken from standard power mains in a sultable and satisfactory manner.

A further object is to provide a system of the character described which will operate without distortion or extraneous noises, and which will produce a clear tone of maximum volume. A further object is to provide a device of the character described which will operate efficiently and satisfactorily with a minimum of power and which shall be simple and eflicient.

Other objects will be in part obvious and will in part appear hereinafter.

The invention accordingly comprises the features of construction, combinations of elements, and arrangement of parts, which will be exemplified in the construction hereinafter set forth and the scope of the application of which will be indicated in the claims.

In modern radio work it is customary to utilize vacuum tubes for the creation and amplification and rectification or detection of radio oscillations, and such tubes utilize sources of unidirectional energy. As it is this energy which is directly converted into sound waves, it is important that it be free from oscillations which may distort the reception. It is usual at the present time, therefore, to employ primary or secondary batteries to furnish this energy.

In accordance with this invention it is possible so to eliminate high frequenc oscil lations that the energy required or the system may be taken directly from power means.

For a fuller understanding of the nature and objects of the invention reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

Figure 1 is a wiring diagram of a system embodying this invention having three tubes arranged to act respectively as detector and twg stages of audio. frequency amplification; an

Fig. 2 is a diagram of a system embodying two stages of radio frequency amplifica- The numeral 1 indicates an aerial connected to the ground as at 2 through a reactance 3 which may be variable as shown at 4 for purposes of tuning. A second reactance 5 coupled to the reactance 3 furnishes a source 0 high frequency oscillations for the system as will be later described. The numerals 6, 7 and 8 represent respectively a detectin tube and first and second stage audio amp ifying tubes. The coil 5 is connected at one side to the grid 9 of the tube 6 through a condenser 10 and grid leak 11 and at the other side to the filament circuit. If desired this latter connection ma be made through a condenser 12 and big resistance 13. A variable condenser 14 may be placed in shunt with the coil 5 for the purpose of tuning it.

JThe radio system here employed may be operated from power lines using either direct current or alternating current. In the latter case the current is first rectified and converted into a. non-pulsating direct current, and thereafter utilized in the system. If direct current is to be employed it may be connected directly to the system without utilizing the rectifying apparatus. For this reason the alternating current system will be first described, thereafter the direct current connection may be readily understood.

The numeral 15 represents generically an alternating current generator, the ener from which is carried to the primary 16 of a transformer 17 having a secondary 18 of a voltage suflicient to serve the plate circuit of the various vacuum tubes and a. power capacity suflicient to serve both plate and filament circuits. As it is ordinarily desirable to utilize both valves of the wave in order to simplify the rectification and the elimination of the oscillations, this secondary 18 is referably split at its center point by provi atap 19. Bytheuseofn.

rectifier in each of the extremes 20 and 21 of the winding l8 :1. pulsatingimidirectional current may be caused to return through the tap 19.

A convenient and ellicient form of rectifier comprises a vacuum tube 22 having'the filament 23 and two anodes 24 and 2;) connected respectively to the terminals 20 and 2t of the winding, 18. The lilamcnt 2?; of this tube is itself fed with energy from a secondary 26 upon the transformer 17 which is also split to provide a central tap 2T connected to a wire 23 which furnishes acommon return for both halves of the wave. There is thus set up upon the wire 29 connected to the tap it) and the wire 28 a unidirectional pulsatin; current.

In order to obliterate fluctuations in the How there is connected in series with one of these wires, as for example the wire 28, an inductance 30 furnishing a path of low resistance tor the direct current but resisting the passage thcrethrough of the fluctuations. A condenser ill may be bridged between the near and 32 of this inductance and the opposite terminal 29 to furnish a short circuit path of low resistance for the fluctuations and another condenser 33 may connect the other side 3t of this inductance with the pole 29 servinp to short circuit again such fluctuations .s pass through the inductance coil. By this arrangement the portions oi? the fluctuations are immediately short circuited by the condenser 31 While the inductance 30 and the condenser 33 in so far as the fluctuating; portion of the current is concerned are in series with each other in shunt across it. In this manner a measure of series resonance exists between the condenser 33 and the inductance 30, building up a high counter electromotire force in the coil 80 to resist the passage of the fluctuation of the current.

The reactance coil 30 is of comparatively high reactance, and in some instances it has been found desirable that the coil have a reactance of approximately 14 henrics while condensers 3t and 33 are of such value as to furnish substantially a short circuit for the high frequency oscillations, condensers ha"- ing a capacity of approximately 11) microfarads having been found suitable. With this arrangement there is provided between the terminals 28 and 34 a direct current c0m paratively free from distortions.

A second reactance having an inductance of substantially the same magnitude as the coil 30 is placed in series between the terminal 34 and the radio circuits to hold back from the radio apparatus the high frequency oscillations in the circuit and the opposite terminal 36 of this reactance furnishes the source of direct current positive energy for the system. A switch 37 may be interposed between the terminal ?A and the inductance 35 and a similar switch 38 may be interposed between the terminal 29 and a terminal 39 constituting the negative terminal of the system.

The filaments 40, 41 and 42 of the tubes 6, T and 8 respectively. are connected in series and one side of the tube 8 is connected through a lead 42% with the negative. terminal I39 while the opposite terminal of the filament ll) is connected by lead -14 with one side 45 of a high resistance -16 connected at its other side with the positive terminal 36. This resistance 46 is preferably adjustable as shown at 47 to permit the adjustment of the current flowing through the filaments.

Under many circumstances the filaments ol' the various tubes will possess sutliciently identical characteristics so that no separate control of the current through them will be required, but such separate control under other circumstances being desirable, may be atlorded by variable resistances -18, 49 and ml in shunt with the filaments. These variable resistances preferably comprise a fixed resistance in permanent shunt across the filament. a portion of which may be short cir cuited as desired. i

Electrical energy for the plate 51 of the tube 6 is derived from a terminal 52 connected through a high resistance with the positive terminal 36, and inserted in series in this circuit is the primary 54 of an audio transformer, A, the secondary 55 of which connects the grid 56 of the tube 7 with the wire -13. The plate 57 of the tube 7 receives its energy from a tap 58 upon the resistance 53 to leave a portion 59 of that resistance in the said plate circuit. This plate circuit has in series with it the primary 60 of a second audio transformer B, the secondary 61 of which connects the grid 62 of the tube 9 with the wire 43.

Three pairs of terminals, 63 and 64, 65 and 66, and 67 and 68. may be provided at any suitable location for connection to the translating device, such as for example as a. telephone or loud speaker, the first pair permitting connection of the translating device direct to the first tube, the second pair furnishing one stage of amplification and the third utilizing both stages of amplification. To this end the terminals 63, 66 and 68 may be connected respectively to the plates of the first, second and third tubes, while the remaining terminals 64, 65 and 67 are connected direct to the terminal 52. An adjustable resistance 69 may be provided in the plate circuit of the last tube to control the volume of sound.

Three condensers 7 O, 71 and 72 are connected in delta formation, one of the terminals of the delta being connected to the negative terminal 39, one to the filament terminal 45 and one to the positive plate terminal 52.

For the purpose of eliminating the high frequency oscillations from the generator of the system it is desirable that one side of the A. C. current shall be grounded as shown at 73, and one of the terminals 28 or 29 is preferably connected to this grounded side through a condenser 74. lVith the apparatus as described the terminal 39 will represent the negative potential of the system.

The resistance 46 will be sutlicient to limit the filament current either with or without the use of the shunt resistance as 48, 49 and 50 to the desired value. Thus the terminal 45 will be at a higher positive potential than the negative return 39. The resistances 53 and 59 will be of such a value, when in series with the plate circuit as described, as to limit the plate current to a predetermined value, and with such an arran ement. particularly if the initial D. C. re tage be materially higher than that required across the plate the resistances 53 and 59 will have the effect of causing a comparatively constant plate circuit to flow in the tubes and this plate circuit operating through the variable resistances from plate to filament of the tube will cause a. varying potential from plate to filament.

The condensers at 71 and 72 may suitably be of the order of one-half microfarads each, Whereas the condenser may suitably be approximately two microfarads.

If it is desirable to utilize the system without the amplifying tubes the translating device may be placed directly across between the terminals 63 and 64, in which case it is in parallel with the primary 54 of the transformer A or if one stage of amplification is desired it may be placed between the terminals 65 and 66 in which case it is connected between the plate 57 and the terminal 52.

In the system illustrated in Fig. 2, two additional tubes are provided for radio frequency amplification. The tube has its grid 81 connected directly to the tuning inductance 205 which is coupled to the aerial inductance 203 and has its plate circuit 82 connected to the primary 83 of a radio frequency transformer C receiving its energy from the terminal 52. The secondary 84 of this radio transformer is directly connected to the grid 85 of the second tube 86 and may be arranged to be tuned as by a variable condenser in multiple with it as shown at 87. The plate 88 of the tube 86 is connected through the primary 89 of the radio transformer D to the terminal 52 and the secondary 90 of this transformer D is connected with the grid 209 of a detector tube 206 through the medium of a. grid condenser 210 and a grid leak 211. The secondary of this transformer D is also provided with a variable condenser 91 for tuningpurposw.

The connections tothe plate circuits of the audio frequency tubes 207 and 208 are simiwith the same voltage as the plate circuits to the amplifying tubes, if desired, by he.

ing connected directly to the terminal 59.

lVith this modification, filaments of all of the tubes may be connected in series but it is desirable that the filaments he placed in such an order and that the grid circuit returns from the various tubes be made to points of such potential as to induce upon the grid of each tube the particular bias most desirable for its operation. a

A convenient and efiective way of producing a practical result is that illustrated in which the filament 93 of the tube 86 and the filament 92 of the tube 80 may be inserted in series between the filament of the detector tube 206 and the filaments 241 and 242 of the tubes 207 and 208 respectively. In this manner the current traverses first the filament 240 of the detector tube and then the filaments 93, 92, 241 and 242 in order.

The grid return from the two radio frequency tubes and from the detector tube may then be made to the wire 94 connectlng the filament 92 with the filament 241. Thus, as illustrated, each of these grids has a nega' tire bias relative to the other filaments, which bias is greatest-upon the detector tube and least upon the tube 80. The grid return from the tubes 207 and 208 may be made directly to the negative side of the system as in the previous modification. With the circuit as shown in Fig- 1 the primary inductance 3 may be tuned in any suitable manner, and the secondary inductance 5 may be tuned by the condenser 14. The oscillatory potential set up in the coil 5 1s impremed upon the grid 9 and the filament 40 through the condensers 10 and 12, and causes corresponding fluctuations in the effective resistance between the plate 51 and the filament. The primary 54 has a direct current flowing through it from the terminal 36 through the resistance 53 and the terminal 52, but by reason of the fact that the terminal 53 is short circuited to the filament through the condensers 71 and 72 fluctuations in the potential across from the plate to the filament may cause a direct oscillatory current between the plate. the primary. the condensers, and back to the filament. Thus a separate pathway is provided for the alternating current circuit and for the direct current circuit through the plate.

The operation of the system 12 of Fig. 2 is similar to the operation of the system in Fig. 1. The particular point at which each individual grid return should be made is dependent upon the particular characteristics of the tube employed but a very great variety is possible due to the fact that any grid return may be connected to any point of the series of filament circuit which produces the proper bias.

Since certain changes may be made in the above construction and diti'erent embodiments of the invention could he made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described. and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A radio system adapted for use from power mains comprising in combination a plate circuit. a iilament circuit and means for b v-passing audio frequency oscillations between the terminals of the filament circuit comprising a large capacity condenser connected across the filament terminals.

2. In a device for the elimination of extraneous noises from a radio set operated from a power main, in combination, three large capacity condensers connected in delta and having terminals adapted to be connected respectively to the terminals of the filament circuit and to the plate circuit of the set respectively.

ii. in a device for the elimination of extraneous noises from a radio set operated from a power main, in combination, three large capacity condensers connected in delta and having terminals, two of which are adapted to be connected to the terminals of the filament circuit of the set and an impedance having one end connected to the third of said terminals and having at the other end of the impedance a terminal adapted to be connected to the power circuit.

4. ln a device for the elimination of extraneous noises from a radio set operated from a. power main. in combination, three large capacity condensers connected in delta. and having terminals, two of which are adapted to be connected to the terminals of the filament circuit of the set and a resistance connected at one end to the third of said terminals and having at the other end of the resistance a terminal adapted to be connected to the power circuit.

5. ln a'device for the elimination of extraneous noises from a radio set operated from a. power main, in combination, three large capacity condensers connected in delta and having terminals, two of which are adapted to be connected to the terminals of the tilament circuit of the set and a resistance connected at one end to the third of said terminals and having at its other end a terminal and a choke reactance connected to the said terminal of said resistance.

(3. In a device for the elimination of extraneous noises from aradio set operated from a power main, in combination, two large apacity condensers connected in series, and two resistances connected together in series and having an inside and two outside terminals, one of the outside terminals adapted to be connected to the plate circuit of a radio set and being connected to one of the condenser terminals, and the other outside terminal being connected to another of the condenser terminals, the third condenser terminal being adapted to be. connected to the negative side of the power main, the intermediate resistance terminal being adapted to be connected to the power side of the positive main.

7. In a device for the elimination ot extraneous noises from a radio set operated from a power main, in combination, two large capacity condensers connected in series, and two resistances connected together in series and having an inside and two out side terminals, one of the outside terminals adapted to be connected to the plate circuit of a radio set and being, connected to one oi" the condenser terminals, and the other outside terminal being connected to another of the condenser terminals, the third condenser terminal being adapted to be connected to the negative side of the power main, and a choke coil connected to said intermediate resistance terminal and adapted to he connected to the positive side of the power main.

8. A radio set adapted for operation direct from uni-directional power mains without extraneous noises, comprising, in combination, a plurality of radio tubes having their filaments in series and plate circuits including translating devices, a large capacity condenser connected across said series of lilaments and a large capacity condenser connecting each terminal of said series of lilaments with the plate circuits beyond the translating devices.

9. A radio set adapted for operation direct from uni-directional power mains without extraneous noises, comprising, in combination, a plurality of radio tubes having their filaments in series and plate circuits including translating devices and a large capacity condenser connected across said series of lilaments and a large capacity condenser connecting each terminal of said series of lilaments with the plate circuits beyond the translating devices and a resistance having one side connected to the positive side of the filament circuit and adapted to be connected by its other side to the positive side of the power main.

10. A device of the character described accuses for operating a radio circuit from a uni-di rectional source of power comprisin an electron tube having a two terminal cat iode and a plate circuit, an impedance connected at one end to said plate circuit and having a terminal adapted for connection to the positive side of source of power and means for lay-passing audio frequency currents between the terminals of the cathode comprisinglarge capacity condensers connecting the said end of said impedance with each of the cathode terminals.

11. A device of the character described for operating a radio circuit from a uni-directional source of power comprising an elec tron tube having a two terminal cathode and a plate circuit, an impedance having one end connected to said plate circuit and having a terminal adapted for connection to the positive side of source of power and a. large capacity condenser connecting the said end of said impedance with a cathode terminal and a large capacity condenser connecting terminals of said cathode.

12. A device of the character described for operating a radio circuit from a uni-directlonal source of power comprising an electron tube having a two terminal cathode and a plate circuit, an impedance having one end,

connected to said plate circuit and having a terminal adapted for connection to the positive side of source of power and a large capacity condenser connecting the said end of said impedance with both terminals of said cathode and a large capacity condenser connecting terminals of said cathode.

13. A device of the character described for operating a radio circuit from a uni-directional source of wer comprising a plurality of electron tubes having their cathodes connected in a series each of said tubes having a plate, a translating device for each of said tubes having one terminal connected to said plate and an outer terminal, a. condenser connecting each of said outer terminals with both terminals of said cathode and a large capacity condenser directly connecting the terminals of the cathode circuit.

14. A device of the character described for operating a radio circuit from a uni-directional source of power comprising an electron tube having a cathode and a plate circuit, a plate circuit resistance connected at one end to said plate circuit and a cathode resistance connected at one end to said cathode both of said resistances having their other terminals connected together, and two large capacity condensers one for connecting the said end of said plate circuit resistanc with each cathode terminal. a

15. A device of the character described for operating a radio circuit from a uni-directional source of power comprising an electron tube having a cathode and a. plate circuit,' a plate circuit resistance connected at one end to said plate circuit and a cathode resistance connected at one end to said cathode both of said resistances having their other terminals connected together, and two large capacity condensers one for connecting the said end of said plate circuit resistance with each cathode terminal and a lar e capacity condenser for connecting the catlode terminals.

16. A device of the character described for operating a radio circuit from a uni-directional source of power comprising an electron tube having a cathode and a plate circuit, a plate circuit resistance connected at one end to said plate-circuit and a cathode resistance connected at one end to said cathode both of said resistances having their other terminals connected together, and two large capacity condensers one for connecting the said end to said plate circuit resistance with each cathode terminal and a choke coil for connecting said terminals to the positive side of the power supply.

17. A device of the character described including in combination a plurality of electron tubes in cascade amplification, means for feeding the plate circuits of said tubes with energy from a generator source of power, said source including means for maintaining a substantiall constant unidirectional electrical supp y, a resistance havin one terminal connected to the positive side of the source of power and having another terminal connected to the plate circuits of said tubes, said resistance being of such ma nitude as to create a substantial voltage rop across itsterminals while in use whereby the plate circuits of said tubes may be supplied with a current of a materially lower voltage than said source of power and means for substantially short circuiting all audio-frequency currents from the source of power comprislng a condenser of not less than one half micro-fared connecting said other terminal of said resistance with the cathodes'of the tubes.

18. A device of the character described including in combination a plurality of electron tubes in cascade amplification, means for feeding the plate circuit of said tubes with energy from a generator source of power, said source including means for maintaining a substantially constant uni-directional electrical supply, a resistance having one terminal connected to the positive side of the source of power and having another terminal connected to the plate circuits of the tubes of the earlier stages of amplification, said resistance bein of such magnitude as to create a substantial voltage drop across its terminals while in use whereby the plate circuits of said earlier tubes may be supplied with a current of a materially lower voltage than said source of power and means for substantially short circuiting all audio-frequency currents from the source out extraneous noises comprising in combio l' power comprising a condenser of not less nation a plurality of electron tubes having than one half micro-fared connecting said their filaments in series and plate circuits other terminal of said resistance with the including translating devices and means cathodes of the tubes, and a tap on said rccomprising large capacity condensers for 5 sistancc for i'nrnishin; a higher voltage cursubstantially short circuiting all audio-frerent to the tubes of the later stages of amquency oscillations between the terminals of plitication. the filament circuit and the plate circuit.

19. A radio set adapted for operation diin testimony whereof I nfi'ix my signature. 1U rect from uui-dircctional power mains witl1- SAMUEL P. LEVENBERG.

CERTIFICATE OF CORRECTION.

Patent No. 1,670,893. Granted May 22, 1928 to SAMUEL P. LEVENBERG.

it is hereby certified that the name of the assignee in the above numbered patent was erroneously written and printed as "The Levenbnrg Corporation" Whereas said name should have been written and printed as "The Lavenburg Corporation"; page 1, line 106. for the word "valves" read "halves; page 4, line 8 5. claim 6, for the word "power" read "positive", and line 86, for the word "positive" read "power"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of January, A. D. 1929.

M. J. Moore, (Seal) Acting Commissioner of Patents.

DISCLAIM ER 1,670,893.-Samuel P. Le zrenberg, New York, N. Y. ELECTRICAL SYs'rnM. Patent dated May 22, 1928. Disclaimer filed May 18, 1931, by the nssignee, Radio Corporation of America. i

Hereby enters this disclaimer to c aim 1 in the said specification which is in the following words, to wit:

A radio system adapted for use from power mains com rising in combination a. plate circuit, a filament circuit and means for by-pessing nu io frequency oscillations between the terminals of the filament circuit comprising a large capacity condenser connected across the filament terminals.

[Qfiicial Gazette June .9, 1931.]-

all audio-frequency currents from the source out extraneous noises comprising in combio l' power comprising a condenser of not less nation a plurality of electron tubes having than one half micro-fared connecting said their filaments in series and plate circuits other terminal of said resistance with the including translating devices and means cathodes of the tubes, and a tap on said rccomprising large capacity condensers for 5 sistancc for i'nrnishin; a higher voltage cursubstantially short circuiting all audio-frerent to the tubes of the later stages of amquency oscillations between the terminals of plitication. the filament circuit and the plate circuit.

19. A radio set adapted for operation diin testimony whereof I nfi'ix my signature. 1U rect from uui-dircctional power mains witl1- SAMUEL P. LEVENBERG.

CERTIFICATE OF CORRECTION.

Patent No. 1,670,893. Granted May 22, 1928 to SAMUEL P. LEVENBERG.

it is hereby certified that the name of the assignee in the above numbered patent was erroneously written and printed as "The Levenbnrg Corporation" Whereas said name should have been written and printed as "The Lavenburg Corporation"; page 1, line 106. for the word "valves" read "halves; page 4, line 8 5. claim 6, for the word "power" read "positive", and line 86, for the word "positive" read "power"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of January, A. D. 1929.

M. J. Moore, (Seal) Acting Commissioner of Patents.

DISCLAIM ER 1,670,893.-Samuel P. Le zrenberg, New York, N. Y. ELECTRICAL SYs'rnM. Patent dated May 22, 1928. Disclaimer filed May 18, 1931, by the nssignee, Radio Corporation of America. i

Hereby enters this disclaimer to c aim 1 in the said specification which is in the following words, to wit:

A radio system adapted for use from power mains com rising in combination a. plate circuit, a filament circuit and means for by-pessing nu io frequency oscillations between the terminals of the filament circuit comprising a large capacity condenser connected across the filament terminals.

[Qfiicial Gazette June .9, 1931.]-

Images