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| Number | Title | Issue Date |
| 4241313 | Audio power amplifier An audio power amplifier comprising a first stage voltage amplifier circuit, a second stage voltage amplifier circuit and a last stage power amplifier circuit. The first stage voltage amplifier circuit is of differential amplifier type including a pair of... | 12/23/1980 |
| 4190805 | Commutating autozero amplifier An active analog signal processing system preferably embodied as an integrated circuit includes a pair of like amplifiers which are alternately switched between a first signal processing mode and a second zeroing mode in which a capacitor in the amplifier... | 02/26/1980 |
| 4189680 | Isolated signal conditioner An isolated signal conditioning circuit is provided whereby control or measurement circuitry is isolated from a load, such as a control instrument, through the use of an optically coupled isolation amplifier. The control or measurement signal is condition... | 02/19/1980 |
| 4186309 | Web monitoring and control apparatus for web handling machinery An improved web monitoring and control apparatus is disclosed for use with web handling machinery, such as printing presses and the like which are of the type that have a generally continuous web of material being printed or otherwise processed. The appar... | 01/29/1980 |
| 4184124 | Operational amplifier An operational amplifier wherein each of the active elements is comprised of complimentary coupled pairs of insulated gate type field effect transistors is provided. A first active stage and a second active stage are coupled together to perform a predeter... | 01/15/1980 |
| 4182993 | Signal amplitude compression system A system for compressing an electrical input signal so that the output signal is related to the input signal in accordance with a predetermined continuous gain function exhibiting (1) fixed gain where the input signal is below a predetermined set threshol... | 01/08/1980 |
| 4182992 | Pulse width modulated signal amplifier A pulse width modulated signal amplifier includes first and second switching transistors and a diode which are connected in series across a DC power source and in the forward direction with respect to the polarity of the DC power source, the diode being c... | 01/08/1980 |
| 4180780 | Input decoupling circuit for transistor differential amplifier A transistor amplifier circuit is arranged in a differential amplifier incorporated into a power amplifier output circuit having approximately unity voltage gain and capable of feeding high current and power outputs to a load in response to high level vol... | 12/25/1979 |
| 4179620 | Crossover arrangement for multiple scanning arrays A line scanning apparatus employing a multiplicity of linear arrays, the linear extent of which is less than the length of the scan line. To permit an entire line to be covered, the arrays are offset from one another in the direction of scan with adjoinin... | 12/18/1979 |
| 4179621 | Scanning apparatus A line scanning apparatus employing a multiplicity of linear arrays, the linear extent of which is less than the length of the scan line. To permit an entire line to be covered, the arrays are offset from one another in the direction of scan with adjoinin... | 12/18/1979 |
| 4179665 | Switched capacitor elliptic filter A switched capacitor sampled data elliptic filter for data transmission or communication systems is disclosed. The filter section comprises three integrating operational amplifiers connected in series with a negative feedback connection between the output... | 12/18/1979 |
| 4179666 | Method and circuit for controlling the output signal of a variable control circuit The output voltage of a variable control circuit, such as a variable gain amplifier, (20, FIG. 1), is controlled by a circuit interconnected in the feedback circuit of the amplifier. The circuit determines whether the output voltage falls within a predete... | 12/18/1979 |
| 4179668 | HF-amplifier circuit A high frequency amplifier circuit comprising a gated field effect transistor operated in common gate configuration with one of the two gate electrodes connected to the substrate of the field effect transistor. Transistors using two insulated gates or hav... | 12/18/1979 |
| 4179667 | Circuit arrangement for adjusting the volume of an automobile radio receiver in dependence on road noise The invention relates to a circuit arrangement for adjusting the volume of an automobile radio receiver in dependence on road noise, comprising a microphone which picks up the noise and emits an electric signal which is conducted by way of an amplifier, a... | 12/18/1979 |
| 4178556 | Class D amplifier system In a Class D amplifier system comprising a pulse width modulator for pulse width modulating with an audio signal a carrier signal having a frequency higher than that of the audio signal, an output switching amplifier connected to the modulator, and a lowp... | 12/11/1979 |
| 4175257 | Modular microwave power combiner A modular microwave power combiner having a plurality of identical microwave diode amplifier circuits grouped in sets within the body of a modular unit which are electrically coupled in parallel to a central cavity sized to be resonant at a single frequen... | 11/20/1979 |
| 4173739 | Overload detecting circuit for a PWM amplifier An overload detecting circuit for a PWM amplifier includes an output current detecting circuit and an output voltage detecting circuit. The output of the output voltage detecting circuit is supplied to a rectifying circuit having a discharge time constant... | 11/06/1979 |
| 4173740 | Speaker protection circuit A speaker protection circuit comprises a detection circuit connected to the output of a power amplifier circuit and detecting overvoltage exceeding a predetermined level developing at the output, and a first relay circuit to disconnect a loudspeaker from ... | 11/06/1979 |
| 4172999 | Self-biasing amplifier stage A self-biasing amplifier stage including a first transistor arranged as a common emitter amplifier. A current amplifier is connected for receiving collector current from the first transistor responsive to which an output current is provided which is diffe... | 10/30/1979 |
| 4172221 | Circuit arrangement for automatically closing a switching transistor for a predetermined time period after opening a switching means A light-emitting diode of a photo-coupler is energized and de-energized through a connection to a switching means. Radiation from the light-emitting diode directed toward a photosensitive means of the photocoupler, reduces the resistance of the photosensi... | 10/23/1979 |
| 4170761 | Remotely powered intermediate amplifier for communications transmission A remotely powered intermediate amplifier for communications transmission incorporates two sectional amplifiers and a filter circuit interconnecting the output of the first sectional amplifier with the input of the second sectional amplifier.... | 10/09/1979 |
| 4169996 | Operational amplifier with slew recovery enhancement Improved slew recovery in a composite driving amplifier for driving a substantially reactive load including a feedback loop to the operational amplifier from the load for regulating the output of the amplifier, the composite amplifier has a predetermined ... | 10/02/1979 |
| 4168472 | Variable gain controller A variable gain controller comprising an amplifier having a feed back terminal which is connected to a variable resistor including a current controller for controlling current flowing through the variable resistor, a filter connected to the variable resis... | 09/18/1979 |
| 4167710 | Pulse width modulated signal amplifier with protective means A pulse width modulated signal amplifier comprises a DC power supply for rectifying an AC input voltage to produce a pair of DC voltages of opposite polarity, a pulse width modulated signal amplifying circuit supplied with a pulse width modulated signal t... | 09/11/1979 |
| 4167708 | Transistor amplifier A transistor amplifier comprises an input stage circuit and an output stage circuit direct-coupled to the input stage circuit: the input stage including complimentary paired transistors having bases commonly connected to an input terminal and emitters AC-... | 09/11/1979 |
| 4167709 | Push-pull amplifier output circuit A high frequency push-pull amplifier which includes an improved output circuit to eliminate spurious emissions, typically low frequency parametric oscillations. The output circuit includes a low pass filter with an inductive input so as to avoid a series ... | 09/11/1979 |
| 4166982 | Logical circuit reference electric level generating circuitry The circuitry is arranged to develop a highly accurate and stable reference electric level voltage and/or current for distribution to a plurality of logical circuits on a semiconductor chip having of the order of a thousand such circuits thereon. An input... | 09/04/1979 |
| 4166981 | Continuous signal amplitude regulator The present invention concerns the transmission of information, and consists in a continuous regulator responsive to the amplitude of a pilot tone included in the signal whose level is to be regulated, including a variable-gain quadripole through which sa... | 09/04/1979 |
| 4166983 | Circuit for limiting the output voltage of an amplifier A circuit permits the output voltage of an amplifier to be limited for certain ranges of its input voltage by causing the amplifier to saturate for said ranges of its input voltage by reducing the power supply. The invention is applicable, for example, to elim... | 09/04/1979 |
| 4166214 | Optical-electrical system for monitoring filaments, wires, strands, tapes and the like The present invention relates to an optical-electrical system for monitoring filaments etc. of narrow, fine configuration by means of an optical sensor, which includes one light guide mounted between a light source and the region monitored in which the fi... | 08/28/1979 |
| 4165494 | Bi-state linear amplifier A bi-state linear amplifier is provided which, in response to a first state of a control signal, functions as a linear amplifier, and in response to a second state of a control signal, is cut off to define a high output impedance. The amplifier includes a... | 08/21/1979 |
| 4164686 | Load current pulse control devices A device for controlling the termination of light emission by a flash device including means for detecting the light reflected from the subject being illuminated by the flash, integrating means connected to the detecting means for providing a flash termin... | 08/14/1979 |
| 4163198 | Audio amplifier An audio amplifier including a non-inverting amplifier stage that provides linear amplification without loop feedback for low distortion audio systems. The amplifier stage includes a triode vacuum tube or a triode connected pentode vacuum tube and a P cha... | 07/31/1979 |
| 4163197 | Audio-frequency power amplifier In a push-pull power amplifier which amplifies an audio-frequency signal supplied thereto and supplies its output signal to a load, a pair of output transistors constituting the push-pull circuit are alternately turned on and off according to the polarity... | 07/31/1979 |
| 4162456 | Differential amplifying system A differential amplifying circuit eliminates the common mode component of a composite signal consisting of the common mode component and a differential component. Two differential amplifiers are coupled to a composite signal source so that one amplifier a... | 07/24/1979 |
| 4162457 | Expansion circuit for improved stereo and apparent monaural image An expander circuit for expanding stereo signals comprises left and right channel variable gain stages whose gain varies in proportion to the amplitude of the control signals fed to the control inputs thereof; and left and right channel expansion control ... | 07/24/1979 |
| 4162398 | Bias control circuit for light modulators A bias control circuit for light modulator includes a feedback control loop through which a measure of the modulated laser beam is processed to derive an error correction signal which is superimposed on the normal bias potential to shift the bias point in... | 07/24/1979 |
| 4160216 | Apparatus for eliminating on-off transitional gain variations in class AB, B and C active element amplifiers A high fidelity audio amplifier having a pair of cooperating active amplifying devices includes two diodes, each of which is connected in a distinct signal pathway directly associated with an active amplifying device so that the amplifier achieves true Cl... | 07/03/1979 |
| 4159449 | Long-tailed-pair with linearization network First and second transistors are connected in long-tailed-pair amplifier configuration, with interconnected emitter electrodes connected to a constant current generator that supplies the tail current. Input signals applied to the base electrodes of these ... | 06/26/1979 |
| 4159422 | Temperature stable displacement sensor with fine resolution A temperature stable displacement sensor with fine resolution having a housing with a radiation source, preferably an LED for generating radiation in the near-infrared region, a lens for collimating the LED radiation into a beam spaced along the axis of t... | 06/26/1979 |
