Active amplifier Q1 is applied to a vertical parabola voltage V 1 , which is generated via a S-shaped capacitor Cv or trace that produces a DC voltage V 2 at an increased voltage level than can be formed by rectifying the parabola voltage. Answer. The increased voltage level is formed in capacitor C5 during some period of each scan. The capacitor is discharged through the parallel resistor R8. In other words, the capacitor voltage increases and decreases during normal scanning but remains above the threshold level (V REF ) as detected by comparator U2. According to the scan loss, the capacitor discharges below the threshold and the comparator Triggers the blanking of the kinescope driver In this way, the phosphors of the cathode ray tubes 10, 11, 12 of televisions, in particular of projection televisions, are protected from combustion due to electron beam deflection losses.
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