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8-2

LC4P_SC

LIST OF CAUTION, NOTES, AND SYMBOLS USED IN THE SCHEMATIC DIAGRAMS ON 
THE FOLLOWING PAGES:

1. CAUTION:

FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, REPLACE ONLY WITH THE SAME TYPE 
FUSE.

2. CAUTION: 

Fixed Voltage (or Auto voltage selectable) power supply circuit is used in this unit.

If Main Fuse (F601) is blown, first check to see that all components in the power supply circuit are not 
defective before you connect the AC plug to the AC power supply. Otherwise it may cause some components 
in the power supply circuit to fail.

3. Note:

1. Do not use the part number shown on the drawings for ordering. The correct part number is shown in the 

parts list, and may be slightly different or amended since the drawings were prepared.

2. To maintain original function and reliability of repaired units, use only original replacement parts which are 

listed with their part numbers in the parts list section of the service manual.

4. Voltage indications on the schematics are as shown below: 

Plug the TV power cord into a standard AC outlet.:

5. How to read converged lines

6. Test Point Information

2

3

1

5.0

5.0

Voltage

Indicates that the voltage 
is not consistent here.

Power on mode

(Unit: Volt)

3

2

1

A

B

C

D

1-B1

1-D3

AREA D3

AREA B1

1-D3

   Distinction 

Area

Line Number 
(1 to 3 digits)

Examples:
1. "1-D3" means that line number "1" goes to the line number
    "1" of the area "D3".   
2. "1-B1" means that line number "1" goes to the line number
    "1" of the area "B1".

: Indicates a test point with a jumper wire across a hole in the PCB.

: Used to indicate a test point with a component lead on foil side.

: Used to indicate a test point with no test pin.

: Used to indicate a test point with a test pin.

Summary of Contents for LT5-S20BB

Page 1: ...SERVICE MANUAL 20 COLOR LCD TELEVISION LT5 S20BB...

Page 2: ...5 1 Electrical Adjustment Instructions 6 1 Block Diagrams 7 1 Schematic Diagrams CBA s and Test Points 8 1 Waveforms 9 1 Wiring Diagram 10 1 Exploded View 11 1 Mechanical Parts List 12 1 Electrical P...

Page 3: ...3 10 75 10 75 10 75 10 3 C N PERFORMANCE 1 1 UHF 21ch UHF 45ch UHF 69ch dB dB dB 15 15 15 18 18 18 4 MULTIPATH a Performance with short delay echoes b Performance with long delay echoes c C N Performa...

Page 4: ...low these specifications Limit specifications represent the absolute worst condition that still might be considered acceptable In no case should a unit fail to meet limit specifications Description Co...

Page 5: ...terminal screw and if applicable to the coaxial connector If the measured resistance is less than 1 0 megohm or greater than 5 2 megohm an abnormality exists that must be corrected before the instrum...

Page 6: ...near thermally hot parts be sure that leads and components do not touch thermally hot parts c the AC supply d high voltage and e antenna wiring Always inspect in all areas for pinched out of place or...

Page 7: ...PVC tubing 3 Spacers 4 Insulators for transistors E When replacing AC primary side components transformers power cord etc wrap ends of wires securely about the terminals before soldering F Observe tha...

Page 8: ...and externally exposed accessible parts RF terminals an tenna terminals video and audio input and output ter minals microphone jacks earphone jacks etc Measuring Method Power ON Insert load Z between...

Page 9: ...the flat pack IC is fixed with glue to the CBA when removing entire flat pack IC first apply soldering iron to center of the flat pack IC and heat up Then remove glue will be melted Fig S 1 6 4 Relea...

Page 10: ...ins of the flat pack IC you can remove it easily Fig S 1 3 2 Affix the wire to a workbench or solid mounting point as shown in Fig S 1 5 3 While heating the pins using a fine tip soldering iron or hot...

Page 11: ...ur due to a potential difference caused by electrostatic charge during unpacking or repair work 1 Ground for Human Body Be sure to wear a grounding band 1 M that is properly grounded to remove any sta...

Page 12: ...otes in the Table Step Loc No Part Removal Fig No Remove Unhook Unlock Release Unplug Unclamp Desolder Note 1 Arm Assembly D1 4 S 1 6 S 2 2 Stand Cover D1 3 Rear Cabinet D1 11 S 3 S 4 4 Function CBA D...

Page 13: ...4 2 A7343DC 3 Rear Cabinet 1 Arm Assembly S 3 S 4 S 3 S 1 S 2 S 3 S 3 2 Stand Cover S 3 Fig D1...

Page 14: ...abinet Speaker Holders 9 Main CBA 7 Jack Holder 8 DVB T Module CBA Unit 13 Speaker S 5 S 13 Earth Plate S 13 S 11 S 9 S 8 S 9 S 11 S 12 S 12 S 10 10 LCD Main CBA Unit Liquid Crystal Panel Unit 6 Tilt...

Page 15: ...N401 CN51B CLN53 CN101A CN102A CN103A CN59 J2 J4 J5 CN103B CN102B CN101B Main CBA CN802 CN53 CN51A CN1001 CN1000 LCD Main CBA Unit To Liquid Crystal Panel Unit To Liquid Crystal Panel Unit To Speaker...

Page 16: ...power off 2 While pressing MENU button press STANDBY ON button on the TV unit To cancel the service mode press STANDBY ON button on the TV unit 3 Press button on the remote control unit to initialize...

Page 17: ...the Service mode Set the each initial data as shown on table 1 below Table 1 Initial Data ITEM BUTTON on the remote control DATA VALU E RF BRT PAL MENU PAL 1 130 RF CNT PAL 170 RF CLR R PAL 80 RF CLR...

Page 18: ...NTSC 88 YC CLR B NTSC 88 YC TNT NTSC 135 YC SHR NTSC 143 RGB BRT NTSC MENU NTSC 4 135 RGB CNT NTSC 190 RGB CLR R NTSC 121 RGB CLR B NTSC 136 RGB TNT NTSC 135 RGB SHR NTSC 143 BRIGHT 0 20 NORMAL 0 55...

Page 19: ...C D S 1 for Red adjustment When x value and y value are not within specification adjust COB C D S 1 or COR C D S 1 Refer to 1 Initial Setting AV1 RGB APL 80 Press 6 button to select C DB C D S 2 for B...

Page 20: ...Press MENU button on the service remote control unit and press 5 on the service remote control selecting YUV BRT mode 3 Make sure that contrast and brightness controls are set to initial position 4 Co...

Page 21: ...J P ON H 117 BUS OPEN PROTECT 1 PROTECT 2 VOLUME INPUT 0 INPUT 1 S VIDEO SW SCL SDA MAIN CBA LCD MAIN CBA UNIT 4 KEY IN 2 CN51B CN53 RESET Q1301 Q1302 AL 3 3V D CN102B CN102A KEY IN 2 1 23 KEY IN 1 2...

Page 22: ...IDEO R 19 VIDEO G 20 VIDEO1 22 CN103A TO LCD BLOCK DIAGRAM CN103B S VIDEO C 2 TU VIDEO 10 VIDEO2 9 CN101A TO LCD BLOCK DIAGRAM CN101B DTV Pb 13 DTV Y 11 DTV Pr 12 S VIDEO Y 3 8 19 20 VIDEO IN1 VIDEO O...

Page 23: ...4 AUDIO R IN 14 IC801 AUDIO AMP 7 VOLUME 11 AMP AMP MUTE STANDBY CONTROL 6 1 R CH L CH 2 JK801 HEADPHONE JACK CN801 SP R 1 SP GND 2 TO SYSTEM CONTROL BLOCK DIAGRAM 3 15 WF1 CL801 SP801 SPEAKER R CH TO...

Page 24: ...B2 19 B3 22 B3 21 B1 18 B1 17 B2 20 STH 8 POL 7 LP 6 VCM 24 V COM 40 V COM 39 CLKV 1 CLEAR 4 OFFEV 3 STV 2 CN1001 PICTURE CONTROL CONTRAST BRIGHTNESS COLOR OFFSET TV SIGNAL PROCESSING SCALER PANEL SI...

Page 25: ...TO LCD MAIN CBA UNIT CN102B 5 6 PANEL 3 3V 7 AL 3 3V D 9 P ON 5V 11 AL 3 3V A Q915 D943 1 5V REG Q903 Q905 SW 3 3V Q910 D936 SW 10 8V Q906 D926 9V REG Q914 Q904 SW 3 3V Q911 Q912 SW 25V Q900 Q302 D30...

Page 26: ...CTOR Q422 423 1 2 CN403 1 2 9 7 3 5 2 6 1 4 10 8 TO POWER SUPPLY BLOCK DIAGRAM TO SYSTEM CONTROL BLOCK DIAGRAM MAIN CBA CURRENT CONTROL SWITCH Q461 Q464 T403 OVER VOLTAGE PROTECTOR Q462 463 9 7 3 5 2...

Page 27: ...in the schematic diagram and the parts list Before replacing any of these components read the parts list in this manual carefully The use of substitute replacement parts that do not have the same saf...

Page 28: ...d 2 To maintain original function and reliability of repaired units use only original replacement parts which are listed with their part numbers in the parts list section of the service manual 4 Volta...

Page 29: ...6 2 17 10 9 18 0 19 3 4 20 3 2 21 0 22 3 5 23 3 5 CN102A 1 3 4 2 2 9 3 3 4 4 0 5 3 4 6 3 5 7 3 5 8 0 9 5 2 10 0 11 3 4 12 0 13 5 2 14 5 2 15 16 4 0 17 0 18 0 19 0 4 20 0 4 21 0 4 22 0 4 23 0 Pin No Vo...

Page 30: ...iagram CN103A 1 0 2 0 1 3 0 5 4 0 5 3 4 6 0 7 0 8 3 5 9 0 3 10 0 8 11 12 0 13 3 5 14 0 1 15 0 1 16 17 3 5 18 3 5 19 0 20 0 2 21 22 1 3 23 0 CN57 1 2 0 3 0 4 0 5 0 6 0 7 0 8 8 0 9 0 6 10 0 11 0 8 12 0...

Page 31: ...8 5 A7344SCM3 Main 3 4 Schematic Diagram...

Page 32: ...y circuit are not defective before you connect the AC plug to the AC power supply Otherwise it may cause some components in the power supply circuit to fail CAUTION For continued protection against fi...

Page 33: ...8 7 Function Schematic Diagram A7344SCF...

Page 34: ...8 8 A7344SCL1 LCD Main 1 2 Schematic Diagram...

Page 35: ...8 9 A7344SCL2 LCD Main 2 2 Schematic Diagram...

Page 36: ...nit If Main Fuse F601 is blown check to see that all components in the power supply circuit are not defective before you connect the AC plug to the AC power supply Otherwise it may cause some componen...

Page 37: ...use a hot chassis ground is present in the power supply circut an isolation transformer must be used Also in order to have the ability to increase the input slowly when troubleshooting this type power...

Page 38: ...12 IR Sensor CBA Top Bottom View Function CBA Top View Function CBA Bottom View BA7343F01021 BA7343F01013 2 Junction A CBA Top Bottom View Junction B CBA Top Bottom View BA7343F01013 4 BA7343F01013 3...

Page 39: ...agram WF1 Pin 14 of IC801 AUDIO 0 1V 0 5ms WF2 Pin 3 of CN103A S VIDEO Y 0 2V 10 s WF3 Pin 2 of CN103A S VIDEO C 0 2V 20 s WF4 Pin 21 of CN102A B 0 5V 5 s WF7 Pin 22 of CN102A VIDEO1 0 2V 20 s WF5 Pin...

Page 40: ...7 26 25 28 29 30 G1 G1 GND STH POL LP GND CLEAR OFFEV STV CLKV G2 G2 G3 G3 GND B1 B1 B2 B2 B3 B3 GND VCM GND PANEL 10 8V PANEL 10 8V PANEL 10 8V GND GND 33 32 31 34 35 37 36 39 38 40 PANEL 25V PANEL 2...

Page 41: ...B1 SP801 SP802 See Electrical Parts List for parts with this mark Main CBA AC601 Function CBA IR Sensor CBA B10 L9 L9 L8 L26 B2 L4 L4 L5 L8 L12 B8 L20 B44 B40 A12 A12 L25 L12 L12 B41 B4 A26 A9 L11 L6...

Page 42: ...11 2 A7344PEX Packing S1 FRONT FRONT S2 S4 Tape Tape Packing Tape S3 X1 Some Ref Numbers are not in sequence X4 X3 Packing Tape Packing Tape S5 X2 5 X2 15 Tape...

Page 43: ...R BTM A7343FP 1EM221637 L2 SCREW P TIGHT M3X8 BIND HEAD GBJP3080 L3 SCREW P TIGHT 3X10 BIND HEAD GBHP3100 L6 SCREW P TIGHT M3 10 WASHERHEAD GCJP3100 L20 SCREW B TIGHT M4X8 BIND HEAD BLK GBHB4080 L26 D...

Page 44: ...ELECTROLYTIC CAP 10 F 50V M CE1JMASTM100 C308 ELECTROLYTIC CAP 10 F 16V M or CE1CMASDL100 ELECTROLYTIC CAP 10 F 16V M or CA1C100SP085 ELECTROLYTIC CAP 10 F 16V M CE1CMASTM100 C402 CHIP CERAMIC CAP 16...

Page 45: ...04 C788 ELECTROLYTIC CAP 100 F 16V M H7 or CE1CMAVSL101 Ref No Description Part No ALUMINUM ELECTROLYTIC CAP 100 F 16V H7 CE1CMAVSM101 C789 ELECTROLYTIC CAP 330 F 6 3V M H7 or CE0KMAVSL331 ALUMINUM EL...

Page 46: ...0K101SP085 ELECTROLYTIC CAP 100 F 6 3V M CE0KMASTM101 C930 CHIP CERAMIC CAP 1608 F Z 0 1 F 25V CHD1EZ30F104 C940 CHIP CERAMIC CAP 1608 F Z 0 1 F 50V CHD1JZ30F104 Ref No Description Part No C941 ELECTR...

Page 47: ...E NDL1001N5399 D615 SWITCHING DIODE 1SS133 T 77 or QDTZ001SS133 DIODE SWITCHING HSS4148TE E QDTZ0HSS4148 D616 DIODE 1N5399 B P or NDLZ001N5399 Ref No Description Part No RECTIFIER DIODE ERB12 06 or QD...

Page 48: ...1SS133 DIODE SWITCHING HSS4148TE E QDTZ0HSS4148 D966 SWITCHING DIODE 1SS133 T 77 or QDTZ001SS133 DIODE SWITCHING HSS4148TE E QDTZ0HSS4148 D967 SWITCHING DIODE 1SS133 T 77 or QDTZ001SS133 Ref No Descri...

Page 49: ...RTK P or NQ1YKTC3875S CHIP TRANSISTOR 2SC3928A T112 1Z or QQ1Z2SC3928A Ref No Description Part No CHIP TRANSISTOR 2SC2412K T146Z QQ1Z2SC2412K Q732 CHIP TRANSISTOR KTC3875S Y RTK P or NQ1YKTC3875S CHIP...

Page 50: ...2 RES CHIP 1608 1 10W F 5 60k RTW5601YF002 R308 CARBON RES 1 4W J 1k RCX4JATZ0102 R309 CHIP RES 1 10W F 4 7k or RRXAFR5H4701 Ref No Description Part No CHIP RES 1 10W F 4 7k or RRXAFR5Z0472 RES CHIP 1...

Page 51: ...CHIP RES 1 10W J 10k or RRXAJR5Z0103 RES CHIP 1608 1 10W J 10k RRXA103YF002 Ref No Description Part No R477 CHIP RES 1 10W J 10k or RRXAJR5Z0103 RES CHIP 1608 1 10W J 10k RRXA103YF002 R501 CHIP RES 1...

Page 52: ...10W J 47k or RRXAJR5Z0473 RES CHIP 1608 1 10W J 47k RRXA473YF002 Ref No Description Part No R780 CHIP RES 1 10W J 47k or RRXAJR5Z0473 RES CHIP 1608 1 10W J 47k RRXA473YF002 R782 CHIP RES 1 10W J 1k o...

Page 53: ...F 360 or RRXAFR5Z3600 RES CHIP 1608 1 10W F 360 RTW3600YF002 R913 CHIP RES 1 10W F 360 or RRXAFR5H3600 Ref No Description Part No CHIP RES 1 10W F 360 or RRXAFR5Z3600 RES CHIP 1608 1 10W F 360 RTW360...

Page 54: ...XH01Z00LY002 FH602 FUSE HOLDER MSF 015 LF B110 XH01Z00LY002 JK721 Y C JACK YKF51 5646N or JYEJ040JC001 JACK SW DIN PCB S 04 DIN 417HA 01 or JYEJ040YUQ03 JACK SW DIN PCB S 04 MDC 076H A LF JYEJ040LY002...

Page 55: ...SKQSAB SST0101AL038 TACT SWITCH TC 1104 H 5 0 or SST0101DNG02 TACT SWITCH KSM0612B SST0101HH003 SW31 TACT SWITCH SKQSAB or SST0101AL038 TACT SWITCH TC 1104 H 5 0 or SST0101DNG02 TACT SWITCH KSM0612B S...

Page 56: ...LT5 S20BB A7344EP 2007 12 20...

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