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公开(公告)号:ZA814533B
公开(公告)日:1982-07-28
申请号:ZA814533
申请日:1981-07-03
Applicant: RCA CORP
Inventor: WILLIS D
Abstract: An inverter applies a square-wave exciting voltage of horizontal deflection frequency to the primary winding of a ferroresonant power transformer. A square-wave alternating polarity output voltage developed across a secondary winding of the ferroresonant transformer is half-wave rectified and applied to an input choke of a horizontal deflection circuit. The input choke is coupled to the series arrangement of a horizontal deflection winding and a trace capacitor. A pincushion correction circuit switching transistor applies a DC voltage to the input choke at a controlled instant within the nonconduction interval of the half-wave rectified output voltage. The peak-to-peak horizontal scanning current is a function of the average voltage developed across the trace capacitor. This average voltage equals the average value of the voltage applied to the input choke. By varying at a vertical rate in a parabolic manner the controlled instant at which the switching transistor applies the DC voltage to the input choke, the peak-to-peak horizontal scanning current is modulated at a vertical rate in a parabolic manner to provide side pincushion correction.
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公开(公告)号:ZA755605B
公开(公告)日:1976-08-25
申请号:ZA755605
申请日:1975-09-03
Applicant: RCA CORP
Inventor: WILLIS D
Abstract: An amplifier for driving a color image reproducing device includes a first transistor the base of which is capacitively coupled to a source of color difference signals. The emitter of the first transistor is direct current coupled to the base of a second transistor. The collector of the second transistor is direct current coupled to the base of the first transistor. The emitter of the second transistor is coupled to a source of a predetermined voltage. The emitter of the first transistor is direct current coupled to the emitter of a third transistor of opposite conductivity type which serves as a luminance signal amplifier. The first and third transistors form a matrix amplifier operative to generate a color signal at the collector of the first transistor. The capacitive coupling device and the second transistor form a clamping circuit for maintaining the voltage developed at the emitter of the first transistor substantially independent of direct current conditions of the source of color difference signals and base-to-emitter voltage variations of the first transistor.
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