Horizontal Scanning Generator

a device for horizontal scanning of a television image. Horizontal scanning generators are used in television cameras and receivers for synchronous and cophasal linear deflection of electron beams in transmitting and receiving cathode-ray tubes. Magnetic deflection of the beam is usually used with deflecting coils, in which the current generated by the horizontal-scanning generator varies nearly linearly to produce sawtooth waveforms.

Like vertical scanning generators, horizontal scanning generators usually contain an oscillator of short-duration pulses whose frequency matches the frequency of line scanning, a circuit to provide the required control voltage, and an output power-amplifier stage, usually with a transformer in the load circuit. In addition to the current feeding the deflecting coils, high-voltage pulses are also taken from the transformer to supply the second anode after rectification. These pulses are used to accelerate and focus the electrodes of the kinescope and extinguish the beam during the retrace along the horizontal.