Circuit for generating a beam current indicative signal.

摘要

In a vertical deflection circuit, a vertical deflection current (iV) is controlled by a vertical sawtooth signal (201). A transistor (78) generates a first control signal (V78) that is derived by sensing the beam current (IR). The control signal is used for modulating the vertical sawtooth signal to compensate for a tendency of the raster height on a screen of a cathode ray tube (66) to increase when the ultor voltage (ULTOR) decreases. The transistor also clamps a second control signal (emitter voltage of 78) that is indicative of the beam current to a predetermined level when the beam current is smaller than a predetermined value. The second control signal is coupled to an automatic beam current limiter (90). <IMAGE>