US2309258A - Amplitude limiter - Google Patents

Description

1943- K. SCHLESINGER 2,309,258

AMPLITUDE LIMITER Original Filed Feb. 26, 1937 Patented Jan. 26, 1943' AMPLITUDE LIMITER Kurt Schlesinger, Berlin, Germany, assignor, by mesne assignments, to Radio Corporation of America, New York, N. Y., a corporation of Delaware Original application February 26, 1937, Serial No. 127,894. .Divided and this application February 11, 1938, Serial No. 190,001. In Germany March Claims.

This invention which is a division of application No. 127,894, now Patent No. 2,190,504, dated Feb. 13, 1940, relates to electrical oscillations and more particularly to a device for equalizing the amplitude of such oscillations having a constant frequency but fluctuating amplitude.

The invention is illustrated according to the accompanying drawing showing a diagram of a connection according to the invention.

The essential part of the device is a double diode ll-which, of course, may be replaced by two simples diodes-having two anodes and 9. directly or indirectly heated cathode. The anodes are connected via coils l2 and I3 and via the common anode resistance It to the positive terminal of a D. C. source. Resistance H may be adjusted by a slider IS. The coils l2 and I3 form a part of transformers I6 and H. To the terminals I9, of the primary l8 of transformer I 6 are conducted the oscillations to be treated whilst the secondary 2| of transformer I! may be connected to a tuned amplifier 22 having output terminals 23, 24.

The operation of the device is as follows:

The current due to the voltage induced by the oscillations in the circuit formed by the coils l2, l3 and the tube can, in both directions, not surpass the current of the respective anode so that all higher amplitudes are cut away. The height of the remaining constant amplitudes may be adjusted by means of the slider IS.

The form of the oscillations so obtained is, of course, not longer sinusoidal. In order to make them sinusoidal the secondary 2| may be connected to the tuned amplifier 22.

I claim:

1. A device for equalizing the amplitudes of oscillations of fluctuating intensity comprising an input and an output transformer, two electronic discharge paths, and adjustable ohmic resistance and a source of direct current, one terminal of the secondary of said input transformer and. one terminal of the primary of said output transformer being connected respectively to one of the anodes of said discharge paths. the two other terminals of said primary and secondary being connected via said resistance to the positive terminal and the cathode of said discharge paths to the negative terminal of said source, said two discharge paths being formed by a tube having a hot cathode and two anodes.

2. A device for equalizing the amplitudes of oscillations of fluctuating intensity comprising an input and an output transformer, two unidirectional current conducting paths each having an input and an output terminal, an adjustable ohmic resistance and a source of direct current, one terminal of the secondary winding of said input transformer and one terminal of I the primary winding of said output transformer being connected respectively to a corresponding terminal of each uni-directional current conducting path, the other two terminals of said primary and secondary transformer windings being connected serially with said resistance and source of direct current to the other terminal of said uni-directional current conducting paths.

3. In combination, a resistor, an electron discharge device having a cathode and a pair of anodes, means for supplying alternating current oscillations between a first of said anodes and said cathode through said resistor, an output circuit connected between a second of said means to rectangular wave form in said output circuit, said last-named means including means for producing a unidirectional potential drop across said resistor.

4. In combination, a pair of unidirectionally conducting circuits, each including a coupling device common thereto and a source of unidirectional potential, said source being so poled in each of said circuits as to cause current to flow in each of said circuits through said coupling device in the same direction, a source of variable alternating electromotive force connected in one circuit, a load device connected in the other circuit, said source of alternating electromotive force increasing current in the unidirectional circuit in which it is connected during one-half cycle and reducing it to zero during the other half cycle, whereby by reason of the coupling of said coupling device the current in the other of said circuits is increased to a predetermined maximum when the current in the first circuit attains zero and the current in the other circuit is reduced to zero by reason of the unidirectional conductivity of said circuit when the current in the first circuit is maximum, the current in said load device being thus limited in magnitude to predetermined values during both half cycles of said alternating electromotive. force.

5. In combination with an electric system from which it is desired to eliminate voltages having a value higher than a predetermined voltage, a tube having a cathode and an anode that is normally positive with respect to the cathode, means for transmitting negative halt-wave currents in the system through the tube in the direction from the anode towards the cathode, means for rendering the anode negative with respect to the cathode upon the occurrence in the system of a voltage higher than the predetermined voltage, and means for rendering the rendering means independent of the magnitude of the predetermined voltage.

6. A static eliminator having, in combination with a receiving system provided with a signalreceiving portion and a signal-delivering portion, a tube having a cathode and an anode and connected with the receiving system so that signals received by the signal-receiving portion shall be transmitted through the tube in the direction from the cathode towards the anode for a positive half wave and from the anode towards the oathode for a negative half wave to the signal-delivering portion, means for maintaining the anode positive with respect to the cathode to a degree less than the voltage corresponding to the static to be eliminated from the signals, and means for maintaining the said degree independent of the average magnitudes of the signals.

'7. In combination with an electric system from which it is desired to eliminate voltages having greater than an undesired magnitude, two means each having a negative terminal and a positive terminal, means for impressing upon the said respective two means voltages of substantially the said magnitude but of opposite polarity, means for transmitting the said voltages through one of the said two first-named means in the direction from the negative terminal toward the positive terminal for a positive half-wave and from the positive terminal toward the negative terminal for a negative half-wave and through the other of the said two first-named means in the direction from the negative terminal toward the positive terminal for a positive half-wave and from the positive terminal toward the negative terminal for a negative half-wave, and means for rendering the positive terminals negative with respect to the negative terminals upon the occurrence in the system of a voltage corresponding to the undesired voltage.

8. In combination with an electric system from which it is desired to eliminate voltages having greater than an undesired magnitude, two means each having a negative terminal and a positive terminal, means for impressing upon the said 7 respective two means voltages of substantially the said magnitude but of opposite polarity, means for transmitting the said voltages through one of the said two first-named means in the direction from the negative terminal toward the positive terminal for a positive half-wave and from the positive terminal toward the negative terminal for a negative halt-wave and through the other of the said two first-named means in the direction from the negative erminal toward the positive terminal for a positive half-wave and from the positive terminal toward the negative terminal for a negative half-wave, and

means for maintaining the positive terminals positive with respect to the negative terminals to a degree less than the voltage corresponding to the undesired voltage.

,9. Apparatus for eliminating undesired peaks from signal voltages having, in combination, means for establishing a current in one direction along a predetermined path to render the path conducting; with the potential established by the current varying from positive to negative from one end of the path to the other end of the path in the said direction, means for transmitting the signal currents along the path between the said ends in the opposite direction, means for maintaining the difference of potential between the said ends 01' the path at a value less than the voltage corresponding to the peaks to be eliminated from the signals, and means for maintaining the said value independent 01' the magnitude of the signals.

10. Apparatus for transmitting voltages not greater than voltages of predetermined magnitude and suppressing voltages greater than the said magnitude having, in combination, two rectifiers each having an anode and .a cathode, means for impressing upon the rectifiers voltages of substantially the said magnitude but of opposite polarity, means for transmitting the said voltages through one of the rectiflers in the direction from the anode to the cathode and through the other rectifier in the direction from the cathode to the anode, and means for rendering the anodes positive with respect to the cathodes upon the occurrence of a voltage of the said magnitude.

KURT SCI-ILESINGER.

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