LG STUDIOWORKS 77M Service Manual page 19

14. Dynamic Focus Output Circuit.
This circuit takes the horizontal and the vertical
parabola waves from the TDA4856(IC701) and
amplifies it to maintain constant focus on center and
corners in the screen.
15. Audio Circuit
MIC circuit sends the microphone sound to PC.
The sound circuit get to the audio gain with the
pre-amp (IC1) and the main amp (IC2).
16. H & V Blanking and Brightness Control.
Blanking circuit eliminates retrace line by supplying
negative pulse to the G1 of the CRT. And Brightness
circuit is used for control of the screen brightness by
changing DC level of the G1.
17. Image Rotation (Tilt) Circuit.
This circuit corrects the tilt of the screen by supplying
the image rotation signal to the tilt coil which is
attached near the deflection yoke of the CRT.
18. Video Pre-Amp Circuit.
This circuit amplifies the analog video signal from 0-
0.7V to 0-4V. It is operated by taking the clamp, R, G,
B drive and contrast signal from the Micom(IC401).
19. Video Output Amp Circuit.
This circuit amplifies the video signal which comes
from the video pre-amp circuit and amplified it to
applied the CRT cathode.