LG Flatron F900B Service Manual page 12

12. High Voltage Output & FBT (Flyback Transformer).
The high voltage output circuit is used for generating
pulse wave to the primary coil of the FBT (Flyback
Transformer (T701)). A boosted voltage (about 27kV)
appears at the secondary of the FBT and it is supplied
to the anode of the CDT.
And there are another output voltages such as the
dynamic focus voltage.
13. H-Linearity Correction Circuit.
This circuit corrects the horizontal linearity for each
horizontal sync frequency.
14. Vertical Output Circuit.
This circuit takes the vertical wave from the
TDA4841(IC801) and performs the vertical deflection
by supplying the saw-tooth wave current from the
TDA4867J (IC601) to the vertical deflection yoke.
15. Dynamic Focus Output Circuit.
This circuit takes H and V parabola wave from the
TDA4841(IC801), and amplifies these waves to offer
to the FBT (T701).
16. H & V Blanking and Brightness Control.
This circuit eliminates the retrace line by supplying a
negative pulse to the G1 of the CDT.
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 to the CDT near the deflection.
18. 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 CDT near the deflection.
19. Moire Reduction Circuit
This circuit reduce interference between the periodical
display pattern and the CDT'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.
20. 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.
21. 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 (IC401).
22. 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 CDT cathode.
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