SERVICE MANUAL WIDE LCD PANEL TELEVISION YA381 2006 LT-20A55SJ, LT-20A55SU TABLE OF CONTENTS PRECAUTION............... . . 1-3 SPECIFIC SERVICE INSTRUCTIONS .
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SPECIFICATION Items Contents Dimensions ( W × H × D ) 53.7cm × 41.4cm × 21.4cm [Included stand] 53.7cm × 37.7cm × 9.7cm [TV only] Mass 6.5kg [Included stand] 5.5kg [TV only] Power Input ADAPTOR AC100 - 240V 50Hz DC24V Power Consumption 80W (Standby: 3.0W) TV RF System...
SECTION 1 PRECAUTION SAFETY PRECAUTIONS [EXCEPT FOR UK] (1) The design of this product contains special hardware, (6) Isolation Check (Safety for Electrical Shock Hazard) many circuits and components specially for safety After re-assembling the product, always perform an purposes. For continued protection, no changes should be isolation check on the exposed metal parts of the cabinet made to the original design unless authorized in writing by (antenna terminals, video/audio input and output terminals,...
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SAFETY PRECAUTIONS [FOR UK] (1) The design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits.
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INSTALLATION 1.3.1 HEAT DISSIPATION 1.3.3 NOTES ON HANDLING If the heat dissipation vent behind this unit is blocked, cooling (1) WHEN TAKING UNIT OUT OF A PACKING CASE efficiency may deteriorate and temperature inside the unit will When taking the unit out of a packing case, do not grasp rise.
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HANDLING LCD PANEL 1.4.1 PRECAUTIONS FOR TRANSPORTATION 1.4.2 OPTICAL FILTER (ON THE FRONT OF THE LCD PANEL) When transporting the unit, pressure exerted on the internal LCD (1) Avoid placing the unit under direct sunlight over a panel due to improper handling (such as tossing and dropping) prolonged period of time.
SECTION 2 SPECIFIC SERVICE INSTRUCTIONS FEATURES ZOOM COLOUR SYSTEM This function can change the screen size according to the If the picture is not clear or no colour appears, change the picture aspect ratio. current colour system to another colour system. OFF TIMER This function can set the TV to automatically turn off after a set time.
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TECHNICAL INFORMATION 2.3.1 LCD PANEL This unit uses the flat type panel LCD (Liquid Crystal Display) panel that occupies as little space as possible, instead of the conventional CRT (Cathode Ray Tube), as a display unit. Since the unit has the two polarizing filter that are at right angles to each other, the unit adopts "normally black" mode, where light does not pass through the polarizing filter and the screen is black when no voltage is applied to the liquid crystals.
SECTION 3 DISASSEMBLY DISASSEMBLY PROCEDURE NOTE: • Make sure that the power cord is disconnected from the outlet. • Pay special attention not to break or damage the parts. • When removing each board, remove the connectors as required. • Taking notes of the connecting points (connector numbers) makes service procedure manageable. •...
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HANDLE SIDE AV DOOR BACK COVER FUNCTION BUTTON SIDE CONTROL PWB AV JACK METAL HANG BRACKET REGULATOR PWB AV JACK PWB BACK DOOR MAIN PWB TERMINAL BRACKET CABLE HOLDER LED PWB LCD PANEL UNIT HINGE COVER DISPLAY SUPPORT FOOT TOP COVER SPEAKER LED LENS FOOT ASSEMBLY...
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MEMORY IC REPLACEMENT • This model uses the memory IC. • This memory IC stores data for proper operation of the video and drive circuits. • When replacing, be sure to use an IC containing this (initial value) data. 3.2.1 SETTINGS OF FACTORY SHIPMENT 3.2.1.1 BUTTON OPERATION 3.2.1.2...
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REPLACEMENT OF CHIP COMPONENT 3.3.1 CAUTIONS (1) Avoid heating for more than 3 seconds. (2) Do not rub the electrodes and the resist parts of the pattern. (3) When removing a chip part, melt the solder adequately. (4) Do not reuse a chip part after removing it. 3.3.2 SOLDERING IRON (1) Use a high insulation soldering iron with a thin pointed end of it.
SECTION 4 ADJUSTMENT ADJUSTMENT PREPARATION (1) The setting (adjustment) using the REMOTE CONTROL UNIT is made on the basis of the initial setting values. The setting values which adjust the screen to the optimum condition can be different from the initial setting values. (2) Make sure that connection is correctly made to AC power source.
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4.2.5 UOCIII SERVICE MODE SETTING ITEMS Item Setting Variable Setting Function items range value Item Setting Variable Setting Function 051 OP BILING items range value 052 OP HP 000 EurAsia TVSub 00.75 053 OP EQUAL 001 Init TV Sets the UOC default values and turns the tv to Stdby 054 OP DOLBY 002 ISP Mode...
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Item Setting Variable Setting Item Setting Variable Setting Function Function items range value items range value 108 PA-TR-TH 0-63 165 LPG 109 PA-LM-TH 166 PGR UOC Red Contrast 0-127 110 PA-ST-TH 167 PGG-CVBS UOC Green Contrast for CVBS input 0-127 111 PA-LO-TH 168 PGG-RGB UOC Green Contrast for RGB input...
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4.3.5 PW SERVICE MODE SETTING ITEMS Setting menu Setting items Setting value Service Submenu 1 UOC Hposition ADC_Calibration UOC_Calibration Service Submenu 2 Panel Type AU_20_WXGA Init NVM PC Mode Burn-In Mode Factory Settings 1 Initial APS Language English Country Model Name Setting items Setting value Setting menu...
SECTION 5 TROUBLESHOOTING This service manual does not describe TROUBLESHOOTING. (No.YA381)1-17...
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Victor Company of Japan, Limited Flat Panel Display Category 12, 3-chome, Moriya-cho, Kanagawa-ku, Yokohama-city, Kanagawa-prefecture, 221-8528, Japan (No.YA381) Printed in Japan...
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Contents For your safety Some DOs and DONTs for you...
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DONT DONT DONT DONT DONT ** Cold cathode fluoresant lamp in LCD PANEL contains a small amount of mercury, please DONT follow local ordinates or regulations for dis- posal. DONT DONT DONT...
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WARNING Fingers may be trapped under the TV causing injuries. Hold the TV at the bottom in the middle, and do not allow it to tilt up or down. The TV may fall causing injuries. Hold the bottom of the stand with your hand and tilt the TV up and down.
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Important Information Please take note EXCLUSION CLAUSE WARNING! NEVER LEAVE A Care and disposal STATIONARY IMAGE ON THE SCREEN...
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Preparation Before Switching on your TV Power connection 8Ãhqhr UÃQPX@S DIQVUÃ98Ã!#ÃW r vhy Features Connections to the RF input socket 67G@ÃUWÃ WÃS@6SÃQ6I@G...
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How to connect other devices Switching the TV ON/OFF To switch the TV on Inserting batteries in the remote control handset To switch the TV off NOTE: Remove the batteries from remote con- trol handset when it is not to be used for a long period.
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Initial Settings Operating the TV First A.P.S. (Automatic You can operate your TV using both the re- mote control handset and onset buttons. Programming System) Operating with the buttons on the 6ÃQÃTÃ 8 6ÃQÃTÃ Ghthtr @tyvu Ãs Ã6ÃQÃTÃ ,1,7,$/ $ 3 6 :$51,1* 3OHDVH &KHFN WKH $QWHQQD &DEOH Operating with Remote Control...
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Menu System Picture Menu Hint: The channel list numbers are assigned by the broad- casters. Because not all channels are broadcast free-to-air and stored by the receiver, the channel list numbers do not run continuously. The fifteenth channel in the list, for ex- ample, may not be channel number 15 but channel number Qvp r H...
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A.P.S. (Auto Programming System) 6ÃQÃTÃ 8 6ÃQÃTÃ Ãs Ã6ÃQÃTÃ Program Table Q t hÃUhiyr D U W " a9 A " ! &...
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$ 3 6 LV UXQQLQJ 3OHDVH :DLW 0HQX! WR H[LW To Display the Time Source Menu T pr @YU @YU T @YU SB7 Sound Indicator @YU! @YU!T 0RQR Ãs à prÃryrpv 6WHUHR 'XDO , Other Features TV Status 'XDO ,, Hyper Sound...
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EXT Modes Picture Mode Sleep Timer Zoom Modes Mute Indicator Volume Bar Note: You can only choose REGULAR and FULL in PC mode...
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PC Mode Installation $ÃQvÃHvvÃ9TiÃ8rp Menu System in PC mode PC Picture Menu Q8ÃQvp r 8 h 7 vtu 8y ÃUrr h r I hy Srr Ãs ÃQ8Ãvp rÃrvt...
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PC Picture Position Menu Q8ÃQvp rÃQvv 6Ã6 wr CÃQvv WÃQvv 9Ã8ypx Quhr &! Ãs ÃQ8Ãvp rÃvv Sound Menu Source Menu T pr @YU @YU T @YU SB7 @YU! @YU!T Ãs à prÃryrpv Sound in PC mode...
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Searching for a teletext page while Teletext watching TV To operate Teletext To Select Double Height Text To Reveal concealed Information To select a page of Teletext To Stop Automatic Page Change To Select Index Page To Select a Subcode Page...
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Peripheral Equipment Connections Via the Euroconnector To exit Teletext Fastext and Toptext RGB mode Via the RCA jacks Via the ANT (aerial) socket Decoder...
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Connecting Headphones Connecting the PC TV and Video Recorder (VCR) To connect to S-Video input NTSC Playback Camera and Camcorder Connect the decoder to the video recorder...
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PC Picture Tips Can not turn the TV on? Sound Can not turn the TV off? Care of the Screen Remote Control Colours of image on screen are abnormal No solution No Image on Display Screen...
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Specifications Model Item LT-20A55SU Broadcasting Systems PAL SECAM BG, DK, I, L, Lp Channels and VHF (VL) : 46,25 MHz - 168,25 MHz Frequencies VHF (VH) : 175,25 MHz - 463,25 MHz UHF : 471,25 MHz - 863,25 MHz Cable TV : (S1-S20/ S21-S41) Input Signal Video: Analog 0,7 Vp-p 75 ohm positive Sync: TTL Level positive or negative, Seperate sync.
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LT-20A55SJ LT-20A55SU STANDARD CIRCUIT DIAGRAM NOTE ON USING CIRCUIT DIAGRAMS 1.SAFETY Type The components identified by the symbol and shading are No indication : Ceramic capacitor critical for safety. For continued safety replace safety ciritical : Metalized mylar capacitor : Polypropylene capacitor components only with manufactures recommended parts.
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CONTENTS SEMICONDUCTOR SHAPES ..............2-2 BLOCK DIAGRAM ..................2-3 WIRING DIAGRAM ..................2-5 CIRCUIT DIAGRAMS MAIN PWB CIRCUIT DIAGRAM ........................ 2-7 SIDE CONTROL PWB CIRCUIT DIAGRAM ..................... 2-17 LED PWB CIRCUIT DIAGRAM ......................... 2-17 AV JACK PWB CIRCUIT DIAGRAM ......................2-18 REGULATOR PWB CIRCUIT DIAGRAM ....................2-18 PATTERN DIAGRAMS MAIN PWB PATTERN ..........................
WIRING DIAGRAM REGULATOR PL103 PL102 PL101 INVERTER UNIT LCD PANEL UNIT PL501 PL175 PL201 PL179 PL176 PL101 MAIN PWB PL403 PL402 PL500 PL104 PL406 PL405 SIDE PL407 AV JACK CONTROL Q505 C SPEAKER SPEAKER LED PWB (No.YA381)2-5 2-6(No.YA381)
CIRCUIT DIAGRAMS MAIN PWB CIRCUIT DIAGRAM (1/5) MAIN PWB ASS'Y (1/5) VE-20237199 NOTE : Refer to the part list for the part number of IC101 and IC102. c17MB18-5-01_0302_1/5_0.0 (No.YA381)2-7 2-8(No.YA381)
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MAIN PWB CIRCUIT DIAGRAM (2/5) MAIN PWB ASS'Y (2/5) VE-20237199 (No.YA381)2-9 2-10(No.YA381)
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MAIN PWB CIRCUIT DIAGRAM (3/5) MAIN PWB ASS'Y (3/5) VE-20237199 (No.YA381)2-11 2-12(No.YA381)
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MAIN PWB CIRCUIT DIAGRAM (4/5) MAIN PWB ASS'Y (4/5) VE-20237199 (No.YA381)2-13 2-14(No.YA381)
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MAIN PWB CIRCUIT DIAGRAM (5/5) MAIN PWB ASS'Y (5/5) VE-20237199 (No.YA381)2-15 2-16(No.YA381)
SIDE CONTROL PWB CIRCUIT DIAGRAM AV JACK PWB CIRCUIT DIAGRAM SIDE CONTROL P.W.B ASS'Y VE-20235650 AV JACK P.W.B ASS'Y VE-20236020 c17TK71_0302_1/1_0.0 c17FAV17-2_0302_1/1_0.0 LED PWB CIRCUIT DIAGRAM REGULATOR PWB CIRCUIT DIAGRAM LED P.W.B ASS'Y REGULATOR P.W.B ASS'Y VE-20247679 VE-20223829 c17LD34-4_0302_1/1_0.0 c17PWI16_0302_1/1_0.0 (No.YA381)2-17 2-18(No.YA381)
AV JACK PWB PATTERN REGULATOR PWB PATTERN [SOLDER SIDE] REGULATOR PWB PATTERN [PARTS SIDE] 2-24(No.YA381)
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Victor Company of Japan, Limited Flat Panel Display Category 12, 3-chome, Moriya-cho, Kanagawa-ku, Yokohama-city, Kanagawa-prefecture, 221-8528, Japan (No.YA381) Printed in Japan...
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PARTS LIST CAUTION The parts identified by the symbol are important for the safety . Whenever replacing these parts, be sure to use specified ones to secure the safety. The parts not indicated in this Parts List and those which are filled with lines --- in the Parts No. columns will not be supplied. P.W.
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CONTENTS USING P.W. BOARD & REMOTE CONTROL UNIT ....................3-2 EXPLODED VIEW-1,2 PARTS LIST ........................... 3-3 EXPLODED VIEW-1 ..............................3-4 EXPLODED VIEW-2 ..............................3-5 PRINTED WIRING BOARD PARTS LIST ........................3-6 MAIN P.W. BOARD ASS'Y (VE-20237199) ....................... 3-6 AV JACK P.W. BOARD ASS'Y (VE-20236020) ....................3-9 SIDE CONTROL P.W.
EXPLODED VIEW-1,2 PARTS LIST Ref.No. Part No. Part Name Description Local VE-20224798 FRONT COVER VE-20181267 LOGO JVC VE-20233912 LENS VE-30034322 SPEAKER (x2) VE-30041596 LCD PANEL UNIT VE-20235932 AV JACK BRACKET VE-20224812 FUNCTION BUTTON ...
EXPLODED VIEW-2 REGULATOR PL103 PL102 PL101 INVERTER UNIT LCD PANEL UNIT PL501 PL175 PL201 PL179 PL176 PL101 MAIN PWB PL403 PL402 PL500 PL104 PL406 PL405 SIDE PL407 AV JACK CONTROL Q505 C SPEAKER SPEAKER LED PWB (No.YA381)3-5...
PRINTED WIRING BOARD PARTS LIST MAIN P.W. BOARD ASS'Y (VE-20237199) Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C109 VE-30012582 CAPACITOR 10nF 50V K C110 VE-30016654 CAPACITOR 100nF 16V K IC100 VE-30027986 C111 VE-30016654 CAPACITOR...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C258 VE-30012568 CAPACITOR 270pF 50V J C366 VE-30012573 CAPACITOR 47pF 50V J C259 VE-30016654 CAPACITOR 100nF 16V K C367 VE-30012573 CAPACITOR 47pF 50V J C260 VE-30016654 CAPACITOR...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C523 VE-30000352 E CAPACITOR 100uF 16V M R226 VE-30012692 RESISTOR 1/16W 4.7K J C524 VE-30000352 E CAPACITOR 100uF 16V M R227 VE-30012510 RESISTOR 1/16W 100R J C525 VE-30000352 E CAPACITOR...
SIDE CONTROL P.W. BOARD ASS'Y (VE-20235650) Ref No. Part No. Part Name Description Local VE-30032684 TACT SWITCH VOLUME + VE-30032684 TACT SWITCH VOLUME - VE-30032684 TACT SWITCH PROGRAM + VE-30032684 TACT SWITCH PROGRAM - VE-30032684 TACT SWITCH MENU VE-30032684 TACT SWITCH TV/AV/OK VE-30032684 TACT SWITCH...
PACKING PARTS LIST Ref.No. Part No. Part Name Description Local VE-50082828 CARTON BOX LT-20A55SJ VE-50083309 CARTON BOX LT-20A55SU VE-20217803 CUSHION ASSEMBLY VE-30039453 REMOTE CONTROL UNIT RM-C1861 VE-50082829 INST BOOK ENGLISH LT-20A55SJ VE-50082875 INST BOOK ENGLISH/GERMANY/FRENCH/ITALIAN LT-20A55SU VE-50082876 INST BOOK SWEDISH/DANISH/NORWEGIAN/FINNISH LT-20A55SU...