Abstract: A folded-cascode amplifier arrangement includes first and second transistors of complementary conductivity type and a constant current generator for supplying quiescent current thereto. Signal current flowing in the first transistor is coupled to the second transistor through current steering at the interconnection between their main conduction paths. The load means for the second transistor includes a cascode-connected third transistor for supplying load current thereto, which third transistor substantially increases the resistance of the load for correspondingly increasing the voltage gain of the amplifier arrangement. The amplifier voltage gain transfer function exhibits a frequency response dominated by a single pole.

Abstract: Within current scaling circuitry having bipolar transistors of the same conductivity type disposed in principal master and slave paths, the negative feedback current gain around the principal master path transistor is regulated in direct proportion with the level of a current source that is independent from both of the principal master and slave paths, to substantially achieve tracking between the level of the current source and the levels of current flow through the principal master and slave paths.

Abstract: A plural-stage amplifier circuit having improved common-mode input voltage range includes first and second transistors connected to form a first long-tailed pair, third and fourth transistors connected to form a second long-tailed pair in cascade connection after the first long-tailed pair, a first current supply providing tail current to the first long-tailed pair, a second current supply having a plurality of outputs providing collector currents to the first long-tailed pair, and a third current supply providing tail current to the second long-tailed pair. The output currents of the first, second and third current supplies are controlled in proportion to a control current which permits the voltage across the third current supply to be controlled such that the first and second transistors do not saturate at input voltages approaching the supply voltage.

Abstract: An amplifier including two long-tailed-pair configurations in cascade: the first including a pair of bipolar transistors having input signals coupled to their respective bases, their emitters connected to a source of quiescent operating current, and their collectors connected to respective constant current generator loads; and the second including a pair of field-effect transistors having gate electrodes coupled to receive signals from the respective collectors of the first and second bipolar transistors, their source electrodes connected to a source of quiescent operating current, and their drain electrodes connected to subsequent circuit means for deriving an output from at least one of them. By this arrangement substantially the maximum available voltage gain is obtained from the first long-tailed pair. The amplifier may be used as the input circuitry of an operational amplifier, for example, and is suitable for monolithic construction.

Abstract: A tuning system for a television receiver includes a phase locked loop (PLL) configuration and an automatic fine tuning (AFT) configuration which are selectively enabled to operate to tune the receiver to nonstandard as well as standard frequency RF carriers which may be provided by cable and master antenna systems. After the selection of a new channel, the operations of the PLL and AFT configurations are sequentially enabled by a mode control apparatus. During the operation of the AFT configuration, an offset detector determines when the frequency of the local oscillator signal is caused to be more than a predetermined offset from its value established during the previous operation of the PLL configuration. In response, the mode control unit reestablishes the operation of the PLL configuration. Channel selection apparatus causes a new channel to be selected after a predetermined number of alternate operating cycles of the two configurations.

Abstract: A signal detection system, of a type suitable for use in line scanning or character recognition apparatus, for providing substantially invariant output signal waveforms in response to repetitive input signals superimposed on pedestal levels. The input signals and pedestal signals may vary substantially. The signal detection system includes a forward signal path including apparatus for amplifying and slicing the input signals, a degenerative feedback path including apparatus for generating a balance signal which is proportional to the amplified difference between an average of the output signals and a reference level, and, the detection system also includes apparatus for subtractively applying the balance signal to substantially eliminate the effects of the pedestal signals on the output waveform.

Abstract: An intercarrier television receiver incorporates circuitry for providing automatic fine tuning signals and frequency translated sound carrier signals. A series-shunt resonant circuit arrangement modifies the passband response of signals provided by an intercarrier IF amplifier and generates both a desired sound carrier to picture carrier relationship and a desired automatic fine tuning response.

Abstract: A supply voltage for signal processing circuits of a television signal processing system is developed in the secondary circuit of a transformer. AC power is coupled to the primary of the transformer through a circuit breaker whose operation is controlled in response to the supply voltage. The circuit breaker includes a normally nonconductive (i.e., high impedance) path which is rendered conductive (i.e., low impedance) with the development of the appropriate supply voltage and rendered nonconductive when the supply voltage falls below a predetermined threshold. A normally conductive (i.e., low impedance) path is coupled across the normally nonconductive path and is rendered nonconductive (i.e., high impedance) as current flows through it. The circuit breaker is particularly useful when the transformer is of the ferroresonant type, since the primary current of a ferroresonant transformer remains substantially constant with changes in the secondary current even under fault conditions.

Abstract: The same AGC voltage as is developed in a television receiver to control the gain of its signal translating stages is additionally utilized by the described circuit to automatically de-peak its video response during the reception of relatively weak signals. The video response is automatically returned to its normal peaked condition during the reception of stronger signals--again, under control of the AGC voltage.

Abstract: An ion current is produced between two spatially separated electrodes by creating a corona discharge about one of these electrodes and causing ions to flow to the other electrode. Aerosols introduced into the region between the two electrodes interact with the flowing ions causing a resultant decrease in ion current. A decrease in ion current is sensed to indicate the presence of aerosols.

Abstract: A voltage controlled tuner in a television receiver is tuned to a desired television channel by sequentially selecting first and second digits representative of a desired channel number. The digits are stored in first and second memory registers from which corresponding analog tuning voltages are developed. Noise immunity circuitry coupled to the memory registers assures accurate registration of the channel digits in the memory registers by minimizing effects of contact bounce and other extraneous noise signals.

Abstract: A delay line suitable for television video signals is included in the luminance channel of a television video signal processing apparatus. A plurality of taps are coupled to the delay line for developing a plurality of delayed video signals. At least a first and a second of the delayed video signals are combined in first combining means to produce a first combined signal which determines the peaking characteristics of the luminance channel. A bandwidth determining signal is derived from at least a third one of the delayed video signals located in time between the first and the second delayed video signal. A second bandwidth determining signal is derived from at least a fourth and a fifth of the delayed video signals located in time between the first and the second delayed video signals. One of the bandwidth determining signals and the first combined signal are combined in a second combining means to produce a second combined signal.

Abstract: An ultrasonic wave transmitter employs a resonant rod to generate an ultrasonic wave in response to the striking of an end thereof by means of a striking member. A striking member support employed for controlling the movement of the striking member relative to the end of the rod is selectively positioned in contact with the end of the rod to provide for damping thereof following each striking.

Abstract: An ion current is produced between two spatially separated electrodes by creating a corona discharge about one of these electrodes and causing ions to flow to the other electrode. Aerosols introduced into the region between the two electrodes interact with the flowing ions causing a resultant decrease in ion current. A decrease in ion current is sensed to indicate the presence of aerosols. A reflecting member reflects aerosols towards the electrodes causing a relatively lengthy interaction between the aerosols and the ion current.

Abstract: A signal amplifier arrangement comprises first and second differential amplifiers coupled in common to a current source which supplies all of the current to the amplifier circuits. Signals to be amplified are coupled between the control electrodes (bases) of the devices in each of the differential circuits by means of voltage follower stages. The main conduction path (collector-emitter) of each of the followers is coupled in series with the main conduction path of the device in the first differential circuit other than the one to the control electrode of which the follower output is coupled. Output signal current is produced in one or more load circuits connected to the second differential circuit, the output signal current being related to the differential input signal voltage but substantially independent of current level induced base-emitter voltage variations in the differential amplifier devices.