Video amplifier circuit: It can be divided into two parts: preview and video output. Preview is sent from the receiving interface of the signal interface. The R, G, and B primary color video signals are amplified to drive the video output stage. The output stage of the video amplifier is the power amplifier: Large-scale, the video signal sent by the preview is amplified to a sufficient power to drive the cathode of the kinescope, and the intensity of the electron beam emitted from the cathode is modulated. After the electron beam bombards the fluorescent screen, the power is completed. A light conversion function, with scanning can display images.
Usually this part of the circuit also has contrast control, line blanking, white balance adjustment and other functions.
Field scanning circuit: It includes two parts: field oscillation and field output. The field oscillation circuit forms a vertical sawtooth wave under the synchronization of the synchronization signal, and the sawtooth wave is then amplified by the field output circuit and then applied to the field deflection coil to form a scanning current.
The function of the field amplitude and field center adjustment is also implemented in the field scanning circuit. In addition, the field frequency sawtooth wave is output to the pincushion correction circuit to correct the horizontal pincushion distortion.
Line scanning circuit: including line oscillation, line output, high voltage circuit, pillow school circuit and other parts.