Sunday, April 29, 2018

LG RF-21FB20R, LG RT-21FB20R - 21 inch CRT TV – Service mode, option adjust, circuit diagram

LG RF/RT-21FB20R/RE/RQ/RX/RW, RF/RT-21FB20V/VE/VG/VQ/VW - MC-019A CHASSIS 
 Used ICs: LA7016, TDA9361/81/70, MSP34100, TDA9859, TDA6107Q, STR-F6654R, LA7840 
Adjustments
Test Equipment required
1. Multimeter (volt meter)
2. Oscilloscope
3. 10:1 PROBE
4. Color Analyzer
CDL Data Adjustment(LINE SVC-0)
1) Press the SVC button to get into the SVC-0 Mode.
2) Press the Channel UP/DOWN button to select CDL12.
3) Press the Volume UP/DOWN button until the CDL data is the same as the Table below.
4) Press the OK(i) button to memorize the data.
OPTION Data Adjustment(OPTION-1,OPTION-2)
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 or OPTION-2.
3) Input the correspond OPTION data referring to Table below with the numeric buttons.
4) Press the OK(¡) button to memorize the data.
Screen Voltage Adjustment
1) Connect the probe of oscilloscope to the RK (Red Cathode) of CPT Board.
2) Set the oscilloscope to 50V/div and 20Us/div and after putting GND line upon the lowest grid line of the scope by pressing GND button, enter into DC mode.
3) Tune the TV set to receive a PAL-B/G 05CH.
4) Adjust Screen Volume of FBT so that the waveform is the same as below.
White Balance Adjustment.(LINE SVC-0)
This adjustment should be performed after screen voltage adjustment.
1) Tune the TV set to receive an 100% white pattern.
2) Press OK(¡) buttons on TV set and remote controller at the same time to get into SVC mode.
3) Press Yellow button on remote controller. (Standard mode)
4) Press Channel UP/DOWN button for desirous function adjustment.
5) Adjust VOL+ or VOL-button in each status of "RG--"/"BG--" for
X=272¡ 8, Y=288¡ 8 with color analyzer.
(Europe Model: X=288¡ 8, Y=295¡ X=272¡ 8, 11,000K)
Schematic [Full]
Power and Deflection section
Deflection Adjustment Procedure
VL (Vertical Linearity)
Adjust so that the boundary line between upper and lower half is in accord with geometric horizontal center of the CPT.
VA (Vertical Amplitude)
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.
Press the OK(¡) button to memorize the data.
Convergence Adjustment
This procedure DOES NOT apply to bonded yoke and picture tube assemblies.
Do not use screen magnets during this adjustment procedure. Use of screen magnets will cause an incorrect display.