| 摘要 |
PURPOSE:To correspond automatically to the change of a vertical frequency by processing a subtraction by a subtracting circuit for which an operational amplifier is used based on two signal voltages from both ends of a vertical S-shape capacitor. CONSTITUTION:The difference of the signal voltages from both ends of a vertical S-shape capacitor C1 of a vertical deflection output circuit 1 is calculated and processed by a subtracting circuit 3 utilized with an operational amplifier 2 (differential amplifying circuit) which is an integrated circuit and a parabola waveform is generated. That is to say, the + terminal of the vertical S-shape capacitor C1 is connected to the non-inversion input terminal (+ terminal) of the operational amplifier 2 through a capacitor 2 and a resistance R2 in series, the + terminal is grounded through a resistance R3, the - terminal of the vertical S-shape capacitor C1 is connected to the inversion input terminal (- terminal) of the operational amplifier 2 through a capacitor 3 and a resistance R4 in series, a resistance R5 is connected between this terminal and the output terminal of the operational amplifier 2, one of the B voltage connecting end of the operational amplifier 2 is connected to a + power source, the other is connected to a - power source, to constitute a parabola waveform generating circuit. Thus, a parabola waveform with little distortion can be easily obtained and the circuit can corresponds to the change of the vertical frequency without changing its constant. |
