Abstract:
A transistor circuit for producing delayed pulses includes a transistor normally biased to conduct. An incoming pulse increases conductivity and charges an RC circuit to change the bias condition. The trailing edge of the incoming pulse drives the transistor to cut-off to form the leading edge of the delayed pulse. The lagging edge of the delayed pulse occurs when the RC circuit discharges enough to allow the transistor to return to normal conductivity.
Abstract:
In reducing crosstalk between the low frequency, frequencyconverted chrominance portions of h-aligned video signals on adjacent tracks, the frequency converting carrier, but not the entire frequency converted portion, has its polarity inverted at the end of each line interval during the recording of alternate tracks but not during the recording of the remaining alternate tracks. This eliminates the extraneous signal that would otherwise be produced in the balanced modulator of the playback apparatus by any direct voltage offset or transient remanent of a direct voltage offset in the recorded signal.
Abstract:
A balanced modulator circuit is provided with first and second differential amplifiers having a pair of inputs and a pair of outputs, respectively. A first input signal is supplied to the pair of inputs of the first and second differential amplifiers, respectively, to drive each of the differential amplifiers differentially and a second input signal is coupled to each pair of inputs in the same phase. The signal coupled to one pair of inputs for the first differential amplifier is the reverse phase with respect to the signal coupled to the pair of inputs of the second differential amplifier. As a result, the product signal of the first and second input signals will be obtained from the output terminals, the pair of outputs of the first and second differential amplifiers being connected to each other.
Abstract:
An automatic phase-control circuit for a reference sub-carrier oscillator of color television receivers, which includes a phase comparing means for comparing a phase of output of the reference sub-carrier oscillator with a phase of a burst signal in a color television signal received by the receiver to control the reference sub-carrier oscillator in synchronism with the burst signal with the phase-compared output. A peak-detector means is provided to detect a peak voltage value of the output of the phase comparing means to produce a direct voltage in response to that value, so that a control signal sufficient for stable and effective control of the reference sub-carrier oscillator is obtained.
Abstract:
A bucket brigaded device is provided which includes first and second clocking signal generators for generating a first set and a second set of clocking signals respectively, a plurality of successive capacitors for sequentially holding charge level representing an input signal, and a plurality of transistors for controlling the transfer of charge levels from one capacitor to another. Each of the transistors is connected between adjacent capacitors. The bucket brigaded device further comprises a first clocking signal driver for supplying one of the first set of clocking signals to each capacitor, and a second clocking signal driver for supplying one of the second set of clocking signals to each transistor.
Abstract:
PCT No. PCT/JP81/00408 Sec. 371 Date Aug. 24, 1982 Sec. 102(e) Date Aug. 24, 1982 PCT Filed Dec. 25, 1981 PCT Pub. No. WO82/02312 PCT Pub. Date Jul. 8, 1982.In order to improve picture quality, an input video signal is added to a correcting signal which is formed by the secondary differentiation of the input video signal. White peak current is reduced so that white blur is avoided without adversely affecting the picture quality on the black side.
Abstract:
A filter circuit of the type utilizing a charge-transfer device, such as a bucket brigade device, comprises a clocking signal drive circuit for supplying a clocking signal; a clock signal generator at whose output a clocking control signal is provided; a transistor whose base is connected to the output of the clock signal generator; a plurality of successive capacitive storage stages for sequentially holding a charge level representing a time-sampled input signal, each of the capacitive storage stages having a clocking electrode for receiving the clocking signal so that the charge level is transferred from one to another of the capacitive storage stages in succession, and at least one of the capacitive storage stages being formed of first and second parallel-connected capacitive circuit portions, and the first and second capacitive circuit portions having respective clocking electrodes coupled to the clock signal generator and to the emitter of the transistor, respectively; and a current feedback circuit, such as a current mirror circuit, for detecting the current flowing through the collector of the transistor and applying a corresponding current to a capacitive storage stage in advance of that stage which is coupled to the emitter of the transistor.
Abstract:
A detector circuit for a color television receiver includes a pair of transistors whose collector-emitter circuits are connected in parallel with each other, an input circuit, such as a differential amplifier, for supplying a differential input signal to the base electrodes of the pair of transistors, an impedance element coupled between the collector electrodes of the pair of transistors and a voltage source, and an integration circuit for integrating a detected signal taken from the collector electrodes of the pair of transistors and thereby providing an output signal. A reference-voltage circuit is included to supply a reference voltage, which can be used as a threshold voltage, to the emitter electrodes of the pair of transistors. The detector circuit is advantageously used in the color demodulating circuit of a color television receiver, wherein an oscillator controlled by color burst signals supplies the input signal to the detector circuit, and the output thereof is used to control the gain of an ACC amplifier.
Abstract:
For improving the frequency characteristic of a color television signal, particularly one in which the chrominance component thereof is provided with a bandwidth substantially narrower than that of the luminance component, the luminance component is used to generate a control signal which is proportional to the lack of registration between low and high frequency portions of the luminance component spectrum, and the control signal thus obtained selectively increases and decreases a delay applied to the relatively narrow-bandwidth chrominance component to substantially align its excursions with the excursions of the relatively wide bandwidth luminance component.