Sawtooth current generator for deflection coil - has thyristor connected across coil and controlled from series commutating inductor

摘要

The sawtooth current generator, for a deflection coil, has a sweep switch consisting of a thyristor (7) and anti- parallel diode (8) connected via a supply capacitor across the deflection coil (9). The coil is connected in series with two further capacitors (4, 6), a commutating inductor (3) and an input inductor (1) across the supply poles. The control pulses for the sweep thyristor are obtained from the commutating inductor via a rectifier (11) and RLC circuit. The first peak from the commutating inductor charges a parallel capacitor (12) which discharges into a capacitor (14) in the RLC circuit. This latter capacitor discharges through a shunt resistor (19) and causes the appropriately poled pulses to be applied to the thyristor.