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公开(公告)号：KR800000295B1
公开(公告)日：1980-04-10
申请号：KR750001981
申请日：1975-09-05
Applicant: RCA CORP
Inventor： WILLIS D
IPC: H01J29/52
Abstract: Amplifier for driving a color image reproducing device comprises a first transistor(46a) whose base is capacitively coupled to a source of color difference signals. The emitter of the first transistor is DC coupled to the base of a second transistor(48a). The emitter of the second transistor is coupled to a source of a predetd. voltage. The capacitive coupling device(54a) and the second transistor form a clamping cct. for maintaining the voltage developed at the emitter of the first transistor which is substantially independent of DC condition of the source of color difference signals and baseto-emitter voltage variations of the first transistor.
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2.发明授权
公开(公告)号：KR810002134B1
公开(公告)日：1981-12-29
申请号：KR780002542
申请日：1978-08-21
Applicant: RCA CORP
Inventor： WILLIS D
IPC: H04N3/18
Abstract: The low voltage power suplies required for parts of a TV receiver such as the oscillator and horizontal deviation control ccts. is derived from the main rectifier cct. during an initial period until the horizontal deviation cct. si operational. The mains supply to a TV receiver is rectified to produce pulsating DC. A filter provides smooth DC output and provides an initial circulating current which passes through a transformer to produce a second AC voltage during this initial period. The secondary winding enables -30 volts to be applied to a second rectifier cct. The voltage varies during the initial period until the permanent operating voltage permits its decoupling from the cct.
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公开(公告)号：KR800000931B1
公开(公告)日：1980-09-12
申请号：KR760001221
申请日：1976-05-18
Applicant: RCA CORP
Inventor： WILLIS D
IPC: H04N3/24
Abstract: A video driver cct. device for controlling the operation of a kinescope(24) is composed of amplifying means(44a) for coupling the video signals to the image reproducing device, clamping means(48a, 54a) coupled to the amplifying means for periodically clamping a predetd. cct. point of the amplifying means to a reference voltage, means for providing a control signal during the horizontal retrace intervals and gating means(62) responsive to the control signal for coupling the reference voltage from the means for providing a direct voltage to the clamping means during the horizontal retrace intervals.
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公开(公告)号：US3742376A
公开(公告)日：1973-06-26
申请号：US3742376D
申请日：1971-07-06
Applicant: RCA CORP
Inventor： WILLIS D
CPC classification number: H04N9/67
Abstract: A transistor video amplifier employs coupling from a collector load potentiometer to an emitter common terminal. The variable arm of the potentiometer is coupled to a peaking capacitor and is further coupled to the emitter electrode through selective networks. At one setting of the potentiometer maximum peaking is obtained by an AC ground provided for the selective networks, and at a second setting the capacitor shunts the collector to depeak the response. The emitter circuit of a transistor video amplifier includes a contrast control which serves to change the gain of the transistor amplifier while maintaining constant peaking. This is afforded by using a bypass capacitor for increasing gain while further serving to introduce a second resonant circuit in shunt with a first circuit via the same capacitor. These circuits may also be advantageously combined in a single video amplifier.
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公开(公告)号：US3795762A
公开(公告)日：1974-03-05
申请号：US3795762D
申请日：1972-01-17
Applicant: RCA CORP
Inventor： WILLIS D
Abstract: A television receiver is disclosed which is capable of operating in any one of a plurality of modes. The receiver has circuitry enabling it to respond to a conventional radio frequency transmission in one mode. An external monitor mode is available by disabling the receiver''s front end processing circuitry and switching an input terminal of the receiver''s video amplifier to an output terminal of an external amplifier, whose bias is controlled by the receiver''s own keyed AGC circuit. The external biased controlled amplifier injects a signal into the receiver''s video amplifier of a magnitude comparable to the magnitude of a signal appearing in the video amplifier during a radio frequency transmission mode, enabling the receiver circuitry to perform substantially similar. The external amplifier includes peaking circuitry for enabling the receiver to respond to externally injected composite color signals. The external monitor mode further includes provisions for changing the filter bandpass in the horizontal phase control loop to enable the receiver to follow taped horizontal sync. A recording amplifier circuit is provided to enable the user to record on suitable apparatus, a composite signal available in the receiver during an RF transmission, for later playback through the receiver in the monitor mode.
Abstract translation: 公开了能够以多种模式中的任何一种操作的电视接收机。
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Patent Agency Ranking6.发明授权Horizontal oscillator control for plural operating mode television receivers 失效用于多种操作模式电视接收机的水平振荡器控制
公开(公告)号：US3740489A
公开(公告)日：1973-06-19
申请号：US3740489D
申请日：1971-12-13
Applicant: RCA CORP
Inventor： WILLIS D
Abstract: A television receiver is disclosed which is capable of operating in any one of a plurality of modes. The receiver has circuitry enabling it to respond to a conventional radio frequency transmission in one mode. An external monitor mode is available by disabling the receiver''s front end processing circuitry and switching an input terminal of the receiver''s video amplifier to an output terminal of an external amplifier, whose bias is controlled by the receiver''s own keyed AGC circuit. The external biased controlled amplifier injects a signal into the receiver''s video amplifier of a magnitude comparable to the magnitude of a signal appearing in the video amplifier during a radio frequency transmission mode, enabling the receiver circuitry to perform substantially similar.
Abstract translation: 公开了能够以多种模式中的任何一种操作的电视接收机。
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公开(公告)号：SE372685B
公开(公告)日：1974-12-23
申请号：SE631271
申请日：1971-05-14
Applicant: RCA CORP
Inventor： WILLIS D
Abstract: 1351703 Colour television RCA CORPORATION 13 May 1971 [15 May 1970] 14769/71 Heading H4F Apparatus for stabilizing the biasing point of an amplifier circuit, such as a matrixing transistor 80 (81 or 82) in a colour television receiver in which a chrominance signal is applied to its base and luminance signal from transistor 70 (which also forms part of the amplifier circuit) is applied to its emitter, to maintain the voltage level at its output (collector electrode) constant, comprises a bias transistor 103 with its base coupled via capacitor 102 to its collector, which is coupled to the emitter of the transistor 80, via capacitor 110 to a source of positive horizontal blanking pulses, and via diode 107 to the output collector electrode of amplifying transistor 80. The horizontal blanking pulses cause both the diode 107 and transistor 103 to conduct, the diode 107 conducting in accordance with the potential on the output collector of transistor 80 and causing capacitor 110 to charge accordingly. The resulting voltage on capacitor 110 determines the voltage across capacitor 102. Capacitor 102 operates to maintain conduction of transistor 103 relatively constant and thus causes the transistor 103 to shunt current from transistor 80 via the emitter of transistor 80 to maintain the collector of transistor 80 at a fixed voltage level. A frequency peaking network is shown in the luminance channel which comprises a transistor 21 with an adjustable resistor 33 coupled to its output collector electrode. Capacitor 36 is coupled between the slider of the resistor 33 and earth, and two resonant circuits 40-42 and 50-52 are coupled in parallel between the junction 35 (of the slider of the resistor 33 and the capacitor 36) and the emitter of transistor 21. A second variable resistor 43 is connected in series with the resonant circuit 50-52 and comprises a contrast control. When the slider of resistor 33 is adjacent the collector of transistor 21, capacitor 36 shunts the collector of transistor 21 and reduces the high frequency response thereof. When the slider is coupled to the supply voltage source Vc the resonant circuits are grounded for A.C. signals. A capacitor 45 is coupled between one end of resistor 43 and the adjustable slider and when the slider is adjacent the emitter of transistor 21 the resistor 43 is by-passed and transistor 21 is operated at maximum gain while maintaining the peaking constant. Horizontal blanking pulses are fed via a diode 56, and vertical blanking pulses are fed via a diode 62, to the collector of transistor 21, a diode 64 being connected across peaking resistor 33. Thus during the horizontal and vertical blanking pulses the voltage at the collector of transistor 21 tends to increase towards Vc, the peaking resistor 33 being by-passed. The slider of resistor 78 comprises a brightness control for the luminance channel.
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8.发明专利
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公开(公告)号：SE327036B
公开(公告)日：1970-08-10
申请号：SE510968
申请日：1968-04-17
Applicant: RCA CORP
Inventor： WILLIS D
Abstract: 1,198,206. Television.R.C.A. CORPORATION. 29 May, 1968 [29 May, 1967], No. 25642/68. Heading H4F. An automatic chroma control (ACC) circuit for a colour TV receiver comprises means for deriving D.C. voltage components from the input and output of a colour-synchronizing- burst gate amplifier and means for controlling the gain of a chrominance amplifier in response to a predetermined combination of the said voltage components. The voltage component from the output of the burst gate amplifier is in practice derived at the grid of a phase locked colour reference oscillator to which the burst signals are applied via a narrow band filter which incidently removes any noise signals. Noise voltages present at the input to the burst gate amplifier, however, are rectified by the grid-cathode diode and produce a negative bias voltage which reduces the gain of the burst gate amplifier. The resulting reduction in the amplitude of the burst voltage applied to the oscillator causes the ACC circuit to increase the gain of the chrominance amplifier and produces an undesired increase in the signals applied to the colour demodulator. This error is minimized by applying the noise generated D.C. voltage component at the input to the burst gate amplifier to the ACC circuit to offset the variation in the voltage derived at the output of the burst gate oscillator. In a first embodiment, Fig. 1, a closed loop ACC arrangement identical to that described in Specification 1,198,207 in which a D.C. voltage component appearing at the grid of a colour reference oscillator 18 is applied via resistor 132 to an ACC circuit 28 comprising a currentcontrolled amplifier the output of which is applied as bias to a chrominance amplifier 12, is modified by connecting the earthy-end of the grid-leak resistor 94 of the burst gate amplifier 14 to the input of the current controlled amplifier. Grid-leak resistor 49 may be selected in value so that the increase in current flowing through it from an increased negative D.C. voltage component at the grid of the burst gate amplifier 14 due to noise compensates for the reduction in the current in grid-leak resistor 132 due to the resulting decrease in the amplitude of the burst signals applied to the oscillator. A second embodiment, Fig. 2 (not shown), comprises an open loop ACC arrangement in which the chrominance amplifier (12) is outside the ACC loop. The grid-leaks of the burst gate amplifier (14) and the reference oscillator (18) are connected directly to ground and the D.C. voltage components at the grids of these valves are applied to the input of a voltage amplifier which provides a bias voltage to control the gain of the chrominance amplifier (12).
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公开(公告)号：NZ191493A
公开(公告)日：1983-02-15
申请号：NZ19149379
申请日：1979-09-06
Applicant: RCA CORP
Abstract: A controllable switch 14 is coupled to a source 10 of unregulated direct voltage and in a closed loop with a filter inductor 16 and a storage capacitor 18 and has its on-off state controlled at the horizontal deflection rate, e.g. by deflection circuit 22, to control the voltage across the capacitor. A diode 24 is coupled with the filter inductor and storage capacitor to form a second series circuit through which current can continue to (ow in the inductor 16 when the controllable switch is opened. The controllable switch is used to regulate the voltage applied to the horizontal deflection circuit 22. A turn-off winding couples a retrace pulse to the switch 14 during each horizontal retrace interval in preparation for the following regulation interval. The current variations in the filter inductor cause the diode to become nonconductive at times, thereby changing the average time during which the filter inductor parallels the deflection winding and varying the retrace pulse duration in such a manner as to improve the regulation.
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