摘要 |
The invention relates to a vertical deflection circuit used in television receivers. U.S. Pat. No. 4,048,544 proposes to derive the vertical deflection voltage by feeding the vertical deflection coil with decreasing portions of the horizontal retrace pulse during the first picture half, and with oppositely directed portions increasing from zero during the second picture half. That method involves very short pulse times and, thus, high voltages and currents to generate the desired deflection power. Therefore, fast thyristors with high blocking voltages must be used. According to the invention, the pulses are taken from the horizontal sweep. Thus, they can be longer and, consequently, smaller even at small currents, and complementary transistors can be used as switching means.
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