LG 29 inch CRT TV – How to enter the service mode, service adjustments, Option settings, full schematic – MC-991A chassis

System control IC:

LG8993-16B(CXP86441-567S) *ASIA.

LG8993-21A(CXP86441-569S) *ASIA.

LG8993-24A(CXP86441-571S) *EU.

TDA4474A,TEA5114, MC14577, ST24C16, TDA4566, TDA4665, TDA8395, TDA8376, MSP3410, TDA2616, CXA2040AQ, TDA4474A, CXD2064Q, LA7845, TDA61O8JF, SE115, SAA5261, GL4558, STR-S6709, SE115, PC123A [optocoupler], 24C04, 6174Z-6005D [SMPS transformer], 151-A10Z [LOT]

Service mode

Press OK buttons on both TV set and Remote Controller at the same time to get into SVC mode.

Deflection Data Adjustment (Line SVC-1)

1. At SVC mode, press the Yellow colored button.  

If the Remote Controller doesn't have the Yellow button, use the button under the Channel Down(PR U) button.
And then, deflection data adjustment OSD (SVC1 mode) will be displayed.
2) Press Channel UP/DOWN button for desirous function Adjustment.
3) Press Volume UP/DOWN button to adjust the data.

VL--(Vertical Linearity)
Adjust so that the boundary line between upper and lower half is in accord with geometric horizontal center of the CPT.
VH--(Vertical Height)
Adjust so that the circle of a digital circle pattern may be located within the effective screen of the CPT.
SC--(Vertical "S" correction)
Adjust so that all distance between each horizontal lines are to be the same.
VS--(Vertical Shift)
Adjust so that the horizontal center line of a digital circle pattern is in accord with geometric horizontal center of the CPT.
HS--(Horizontal Shift)
Adjust so that the vertical center line of a digital circle pattern is in accord with geometric vertical center of the CPT.
EW--(Horizontal Width)
Adjust to that a digital circle pattern looks like exact circle.
EP--(East-west Parabola)
Adjust so that middle portion of the outermost left and right vertical line looks like parallel with vertical lines of the CPT.
EC--(East-west Corner)
Adjust so that the vertical line at every 4 corners of the screen looks like parallel with the vertical lines of the CPT.
ET--(East-west Trapezium)
Adjust to make the length of top horizontal line same with it of the bottom horizontal line.

Hold Down Check(X-ray Protection)
1) Short the both terminal of R430 on the Main2 Board and check if the TV set turns into Stand-by,  It should.

White Balance Adjustment.(LINE SVC 0)
NOTE : This adjustment should be performed after screen voltage adjustment.
1) Tune the TV set to receive an 100% white pattern.
2) Press the Yellow button on remote controller in the SVC Mode (press OK buttons on both TV set and remote controller at the same time) then you can find On Screen Display.
3) Press PSM (RED) button on remote controller. (Standard picture)
4) Press PR+ or PR- button for desirous function adjustment.
5) Adjust VOL+ or VOL- button for Gg31.
6) Adjust VOL+ or VOL-button in each status of "Rg--"/"Bg--" for X=272.8, Y=295.8 with color analyzer (color temperature 11,000oK).

OPTION Adjustment (SVC MODE:OPTION-1, OPTION-2, OPTION-3)
NOTE: When the EEPROM has been replaced, the Option data should be restored as the function of individual system and specification.
1) Press OK buttons on both TV set and Remote Controller at the same time to get into SVC mode.
2) Press the Yellow button several times to find OPTION-1, OPTION-2 and OPTION-3.
3) Input the correspond OPTION data referring to Table below with the numeric buttons 0~9.

Sound Pre scaler
1) Set to Scart when one of AV1 or AV2 is Scart jack.  Audio out level : 500mVrms at 54% modulation ratio
2) Set to Phono when both of AV1 and AV2 is RCA Phono jack.  Audio out level : 500mVrms at 100% modulation ratio.
(NTSC-M : 400mVrms)

MSP3410(3400) Pre-scaler setting

Schematic