US1792275A - Circuits for electron-discharge devices - Google Patents

Description

Feb. 10, 1931. G. w. CARPENTER 7 CIRCUITS FOR ELECTRON DISCHARGE DEVICES Filed Oct. 3, 1923 AAAA - IhQentor: G l enn \A/. Cam-pent er.

His Attorney.

Patented Feb. 10, 1931 UNITED STATES;

GLENN W. CARPENTER, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELEC- PATENT OFFICE {ERIC COMPANY, A CORPORATION OF NEW YORK CIRCUITS FOR ELECTRON-DISCHARGE DEVICES Application filed October 3, 1923. Serial No. 666,223.

My present invention relates to circuits adapted for use with electron discharge amplifiers and detectors, and more particularly to arrangements for eliminating disturblng effects in such circuits due to the use of periodically fluctuating voltage sources of sup- 1 p The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims my invention itself, however, both as to its organization and method of operation will best be understood by reference to the following description taken in connection with the accompanying drawing in which Figs. 1 and 2 show diagrammatically two difierent circuit arrangements whereby my invention may be carried into eflI'ect.

In Fig. 1 I have indicated an electron discharge device 1 having a cathode 2 adapted to emit electrons, two anodes 3 and 4, and two grids 5 and 6. Grid 5 may be employed in the usual manner for controlling the current between cathode 2 and anode 4 by connecting the source of controlling voltage to conductors 7 and 8 in the usual manner for employing the device as an amplifier or as a detector.

Anodes 3 and 4 are connected together and the plate or anode circuit of the device is supplied with current from a direct current generator 9. The use of a direct current generator as a source of plate supply gives rise to disagreeable noises in the telephone receivers 10 in the plate circuit due to commutation ripples, etc., it special means is not provided to eliminate the efi'ect of the voltage fluctuations of the generator. It has been customary in the past to use large and somewhat expensive filter coils for this purpose.

I overcome the effect of the voltage fluctuations of the source 9 by connecting the grid 6 by means of a potentiometer connection to the resistance 11, which is connected adjacent the negative terminal of generator 9. The anodes 3 and 4 are connected by means of another potentiometer connection to a point in resistance 12, which is in series with resistance 11. The cathode 2 is connected to a point 13 between resistances 11 and 12. With 50 this connection any point in resistance 11 will be negative with respect to the junction point 13, and hence the grid 6 will always be negative with respect to the cathode 2.

The operation of the system described is as follows :Assume that the circuit is out of adjustment and that disagreeable noises are heard in the telephone 10 due to the voltage fluctuations of the generator. may then be moved along resistance 11 until a balance is obtained and silence occurs in the tential variations impressed upon grid 6 will The slider.

be of the proper phase to compensate for the variations in plate current due to fluctuations in the voltage of the source 9. If the voltage of source 9 increases the current through resistance 11 will tend to increase and this will cause an increase in the negative potential applied to grid 6. This increased negative potential will in turn counteract the tendency toward an increase in plate current. On the other hand, a decrease in the voltage of source 9 will cause a decrease in the negative potential of grid 6, and permit the current flowing to plate 3 to increase thus counteracting the tendency for the current in the plate circuit to decrease.

In Fig. 2 I have indicated the application of my invention to a radio receiving system comprising three electron discharge devices 14, 15 and 16, having their plate circuits supplied with current from an alternating current source 17 through electron discharge rectifiers 18 and 19. Device 14 is connected to serve as a detector and devices 15 and 16 are provided with two grids 20 and 21. Grids 20 perform the usual function of controlling the current to the plates. The currents supplied to the plate circuits flow through resistance 22 and grids 21 are connected to a point in this resistance by means of the sliding connection 23. The operation of the system shown in Fig. 2 is substantially the same as that of Fig. 1. The fluctuations in the rectified potential supplied to the plates are partly eliminated by the smoothing condenser 24 and the effect of the remaining fluctuations is counteracted by the potentials applied to grids 21.

While I have shown and described only two embodiments of my invention it will be apparent that many modifications in the apparatus and circuit connections employed may be made without departing from the scope of my invention as set forth in the ap pended claims.

What I claim as new and desire to secure by Letters Patent of the United States, is

' l. The combination with an electron discharge device having an electron emitting cathode, an anode and a plurality of grids, of a source of periodically fluctuating voltage connected in the anode circuit, and means for impressing upon a circuit connected between the cathode and one of the grids periodic voltage fluctuations of the proper phase and value to neutralize the efl'cct in the anode circuit of the device of the voltage fluctuations of the source connected therein.

2. The combination with an electron dis charge device having an electron emitting cathode, an anode and a plurality of grids of a source of periodically fluctuating vol age connected in the anode circuit and means for impressing upon the circuit connected between the cathode and one of the grids periodic voltage fluctuations derived from said source of the proper phase and value to neutralize the effect in the anode circuit of the device of the voltage fluctuations of the source connected therein. 3. The combination with an electron dis charge device having an electron emitting cathode, and anode and a plurality of grids, of a source of periodically fluctuating voltage connected in the anode circuit, a resistance in the anode circuit and a connection from one of the grids to a point in said resistance for impressing upon that grid periodic voltage fluctuations of the proper phase and value to neutralize the effect in the anode circuit of the voltage fluctuations oi the source connected therein.

4. The combination with an electron discharge device having an electron emitting cathode, an anode and a plurality of grids of a source of fluctuating voltage connected in the anode circuit, means for impressing upon a circuit connected between the cathode and one of the grids voltage fluctuations of the proper phase and value to neutralize the efl'ect in the anode circuit of the device of the voltage fluctuations of the source connected therein, and means for impressing signalling potentials upon another of said grids.

5. The combination in a system for the reception of signals of an electron discharge device having an electron emitting cathode, an anode and a plurality of grids and circuits connecting said cathode and said anode and grids, one of said grid circuits having connections for receiving currents to be detected and another of said grid circuits having associatcd therewith means for supplying a suitable potential to eliminate undesired currents in the anode circuit.

6. The combination with an electron discharge device having an electron emitting cathode, an anode and a plurality of grids, of a source of rectified alternating voltage connected in the anode circuit, and means for impressing upon a circuit connected between the cathode and one of the grids voltage fluctuations derived from said source and of the proper phase and value to neutralize the effect in the anode circuit of the device of the voltage fluctuations of the source connected therein.

7. The combination with an electron discharge device having an electron emitting cathode, an anode and a plurality of grids, of a source of rectified alternating voltage connected in the anode circuit, and means for impressing upon a circuit connected between the cathode and one of the grids voltage fluctuations derived from said source and of the proper phase and value to neutralize the efiiect in the anode circuit of the device of the voltage fluctuations or" the source connected therein, and means for impressing signaling potentials upon another of said grids.

8. The combination in a receiving system of a plurality of electron discharge devices connected in cascade, each of said devices havin an electron emitting cathode, an anode and a plurality of grids, a source of periodically fluctuating voltage connected in the anode circuits of all of said devices, and means for impressing upon circuits connected between the cathode and one grid of each device periodic voltage fluctuations of the proper phase and value to neutralize the effeet in the anode circuits of the devices of the voltage fluctuations of the source.

9. The combination in a receiving system of a plurality of electron discharge devices connected in cascade, each of said devices having an electron emitting cathode, an anode and a. plurality of grids, a source of rectified alternating voltage connected in the anode circuits of all of said devices, and means for impressing upon circuits connected between the cathode and one grid of each device voltage fluctuations derived from said source of the proper phase and value to neutralize the effect in the anode circuits of the devices of the voltage fluctuations of the source.

10. The combination with an electron discharge device having an electron emitting cathode, an anode and a grid of a source of periodically fluctuating voltage connected in the anode circuit, and means for impressing upon a circuit connected between the cathode and the grid periodic voltage fluctuations of v the proper phase and value to neutralize the .efiect in the anode circuit of the device of the voltage fluctuations of the source connected therein.

11. The combination with an electron discharge device having an electron emitting cathode, an anode and a grid of a source of periodically fluctuating voltage connected in the anode circuit, and means for impressing upon a circuit associated with said device periodic voltage fluctuations of the proper phase and value to neutralize the eifect in the anode circuit of the device of the voltage fluctuations of the source connected therein.

12. The combination'with an electron discharge device having an electron emittin cathode, an anode and a grid of a source 0 fluctuating voltage, a resistance connected between the cathode and anode and a second resistance connected between the cathode and grid, said resistances being connected in series with one another and in shunt to the fluctuating voltage source in such a way that v the voltage drop across the second resistance serves to impress upon the grid a voltage which" is always negative with respect to that of the cathode and which fluctuates in opposite phase with the voltage fluctuations impressed upon the anode.

13. The combination with an electron discharge device having an electron emittin cathode, an anode and a grid of a source 0 rectified alternating voltage connected to the anode circuit of said device, a resistance connected in series with said source and a connectlon to the grld from a point in sald resistance which is always at a negative potential with respect to the cathode, said point being so chosen that the voltage fluctuations produced across said resistance and impressed upon the grid are of such value as to neutralize the effect in the anode circuit of the voltage fluctuations of saidsource.

14. In a system for supplying operating voltages to an electron discharge device having a cathode, an anode and-a grid, a source of periodically fluctuating voltage, a resistance connected to said source and individual connections from each of the electrodes of said device to said resistance, said connections being so made that the potential impressed from said resistance upon the grid is always negative with respect to that of the cathode and fluctuates in opposite phase to the voltage fluctuations impressed upon the anode.

In witness whereof. I have hereunto set my hand this 1st day of October, 1923.

GLENN W. CARPENTER.

-DISOL.AIMER Y 1,792,275.Glenn W. Carpenter, Schenectady, N. Y. CIRCUITS ron ELECTRON- DISCHARGE DEVICES. Patent dated February 10, 1931. Disclaimer filed November 24, 1934, by the assignee, General Electric Company. V

Hereby enters this disclaimer to that part of the'claim in said specification which is in the following words, to wit:

14. In a system for supplying operating voltages to an electron discharge device having a cathode, an anode and a grid, a source of periodically fluctuating voltage, a resistance connected to said source and individual connections from each of the electrodes of said device to said resistance, said connections being so made that the potential impressed from said resistance upon the grid is always negative with respect to that of the cathode and fluctuates in opposite phase to the voltage fluctuations impressed upon the anode.

[Qfic'ial Gazette December 18, 1.934.]

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