LG FLATRON 915 FT PLUS, Service Manual

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14. H-Linearity Correction Circuit.
This circuit corrects the horizontal linearity for each
horizontal sync frequency.
15. Vertical Output Circuit.
This circuit takes the vertical ramp wave form the
TDA4856(IC201) and performs the vertical deflection
by supplying the saw-tooth wave current form the
TDA8172 (IC601) to the vertical deflection yoke.
16. Dynamic Focus Output circuit.
This circuit takes H and V parabola wave from the
TDA4856(IC201) and amplifies these waves to offer to
the FBT(T703).
17. H & V Blanking and Brightness Control.
This circuit eliminates the retrace line by supplying a
negative pulse to the G1 of the CRT. The brightness
control circuit is used to control of the screen
brightness by changing the DC level of G1.
18. Tilt (Image Rotation) Circuit.
This circuit corrects the tilt of the screen by supplying
the image rotation signal to the tilt coil which is
attached to the CRT near the deflection.
19. Static Convergence Control Circuit.
This circuit corrects the convergence of the screen by
supplying the convergence signal to the 4H(STC) coil
which is attached to the CRT near the deflection.
20. Moiré Reduction Circuit.
This circuit reduce interference between the periodical
display pattern and the CRT’s slot (or dot). The
positions of every other one dot video signal beams
(red, green and blue beam) are shifted finely, thus
reducing interference.
21. OSD Circuit.
This circuit is used for performing the OSD (On
Screen Display) function. When a user selects the
OSD Select/ Adjustment control, the adjustment status
displays on the screen.
22. Video Pre-Amp Circuit.
This circuit amplifies the analog video signal from 0-
0.7V to 0-4V. This circuit is operated by taking the
clamp, R, G, B drives, and contrast signals from the
Micom (IC271).
23. Video Output Amp Circuit.
This circuit amplifies the video signal which comes
from the video pre-amp circuit and amplified video
signal is applied to the CRT cathode.