Abstract: Synchronization of a horizontal deflection circuit with horizontal synchronizing signal pulses is obtained by the use of a voltage controlled oscillator (VCO) that is included in a phase-lock loop circuit (PLL). A phase-control loop circuit (PCL) includes a phase detector having a first input terminal that is responsive to an output signal of the VCO and a second input terminal that is responsive to retrace pulses of a horizontal deflection circuit output stage. A sum signal of the phase detector output signal of the PLL and a vertical rate parabola signal is formed upstream of the loop filter of the PLL. Correction of a differential pin distortion is accomplished by dynamically phase shifting the phase of an output signal of the VCO in a vertical rate parabola manner.

Abstract: In order to protect a load from surges which may occur on an AC line, a pair of metal oxide varistors (MOV) are serially coupled across the AC line. A series circuit of a gas tube and a capacitor is coupled from the terminal which joins the two varistors to ground.

Abstract: Synchronization of a horizontal deflection circuit with horizontal synchronizing signal pulses is obtained by the use of a voltage controlled oscillator (VCO) that is included in a phase-lock loop circuit (PLL). A phase-control loop circuit (PCL) includes a phase detector having a first input terminal that is responsive to an output signal of the VCO and a second input terminal that is responsive to retrace pulses of a horizontal deflection circuit output stage. A sum signal of the phase detector output signal of the PLL and a vertical rate parabola signal is formed upstream of the loop filter of the PLL. Correction of a differential pin distortion is accomplished by dynamically phase shifting the phase of an output signal of the VCO in a vertical rate parabola manner.

Abstract: An electron beam tends to slope downwardly as it is deflected horizontally to form a raster in a video display apparatus. The sloping of the beam can cause geometric errors in the raster, for example orthogonality and parallelogram errors. A raster correction circuit substantially offsets the downward slope of the electron beam by modulating a vertical deflection current with an induced horizontal-rate raster correction current, thereby substantially eliminating orthogonality and parallelogram errors in the raster. In respective embodiments of an inventive arrangement taught herein, the horizontal-rate raster correction current is induced in the vertical deflection coils by magnetically coupling a filament pulse waveform, a horizontal deflection voltage waveform, or a horizontal deflection current into the vertical deflection coils.

Abstract: An electron beam tends to slope downwardly as it is deflected horizontally to form a raster in a video display apparatus. The sloping of the beam can cause geometric errors in the raster, for example, orthogonality and parallelogram errors. A raster correction circuit offsets orthogonality and parallelogram errors in a raster by modulating a horizontal deflection current at a vertical scanning rate. The raster correction current is phased in relation to a horizontal-rate deflection current such that scan lines in an upper-half portion of the raster are shifted to the right, and scan lines in a lower-half portion of the raster are shifted to the left.