| 摘要 |
The horizontal frequency control pulses of, respectively, increasing and decreasing pulse widths required by switches which control the transfer of energy from the horizontal output stage to the vertical deflection coils are furnished by a first and second comparator. Each of the comparators is a difference amplifier having an inverting and a direct input. The inverting input of the first comparator is connected only through a resistor to the output of a vertical frequency sawtooth generator and, similarly, only through a resistor, to the output of a stage which furnishes horizontal deflection frequency pulses having slanted pulse tops. The direct input of the second comparator is also connected, through a decoupling resistor only, to the output of the vertical sawtooth generator and, while its inverting input is connected to the output of the stage which furnishes the shaped horizontal frequency pulses. The direct input of the first comparator is connected to receive a DC voltage and to receive the output of a stage which furnishes positive vertical blanking pulses. To stabilize the height of the television picture, the voltage drop across a resistor in series with the vertical deflection coils is applied to the output of the vertical sawtooth generator, so that a negative feedback is provided.
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