An SCR horizontal deflection and high voltage circuit

In the past the use of semiconductors in the horizontal deflection circuitry of television receivers presented one of the most difficult application problems. Several types of germanium and silicon transistors have been used with varying degrees of success. The long turn-off time of these power switching transistors resulted in considerable power dissipation during turn-off, which produced an overall low circuit efficiency as well as power-device unreliability. Although silicon power transistors with suitable switching times are now available which perform well in typical circuits, the present cost of these devices precludes their use in commercial applications.