SECTION 1 PRECAUTION SAFETY PRECAUTIONS (1) The design of this product contains special hardware, (8) When service is required, observe the original lead dress. many circuits and components specially for safety Extra precaution should be given to assure correct lead purposes.
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INSTALLATION 1.2.1 HEAT DISSIPATION If the heat dissipation vent behind this unit is blocked, cooling efficiency may deteriorate and temperature inside the unit will rise. Therefore, please make sure pay attention not to block the heat dissipation vent as well as the ventilation outlet behind the unit and ensure that there is room for ventilation around it.
SECTION 2 SPECIFIC SERVICE INSTRUCTIONS ABOUT LIQUID CRYSTAL DISPLAY 2.1.1 STRUCTURE OF LIQUID CRYSTAL PANEL The Liquid Crystal Display used for this unit is of a TFT (Thin Film Transistor) type panel. The structure of this panel is that a TFT array-formed substrate and the stripe pixel matrix type color filter substrate are pressed together with a liquid crystal filled in between these materials.
SECTION 3 DISASSEMBLY DISASSEMBLY PROCEDURE CAUTION AT DISASSEMBLY: 3.1.1 REMOVING THE STAND ASS'Y (Fig.1) • Be sure to perform the SYSTEM SETTEING, at the end of (1) Remove the HINGE COVER. the procedure. (2) Remove the 4 screws [A], then remove the STAND ASS'Y. •...
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3.1.3 REMOVING THE MAIN PWB SHIELD (Fig.2) • Remove the STAND ASS'Y. • Remove the REAR COVER. (1) Remove the 1 screw [C], then remove the D-SUB COVER. (1) Remove the 1 screw [D], then remove the TUNER COVER. (1) Remove the 2 screws [E], then remove the AV COVER. (1) Remove the 3 claws [F], then remove the MAIN PWB SIDE SHIELD.
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3.1.4 REMOVING THE MAIN PWB (Fig.3) 3.1.5 REMOVING THE INVERTER PWB (Fig.3) • Remove the STAND ASS'Y. • Remove the STAND ASS'Y. • Remove the REAR COVER. • Remove the REAR COVER. • Remove the MAIN PWB SHIELD. • Remove the MAIN PWB SHIELD. (1) Disconnect the connectors [P001], [P004], [P006], [P009], (1) Disconnect the connectors from the INVERTER PWB.
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3.1.6 REMOVING THE LCD PANEL UNIT (Fig.4) 3.1.7 REMOVING THE SPEAKER (Fig.4) • Remove the STAND ASS'Y. • Remove the STAND ASS'Y. • Remove the REAR COVER. • Remove the REAR COVER. • Remove the MAIN PWB SHIELD. (1) Disconnect the connectors from the KEY PWB. •...
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3.1.8 REMOVING THE KEY PWB (Fig.5) 3.1.9 REMOVING THE IR PWB (Fig.5) • Remove the STAND ASS'Y. • Remove the STAND ASS'Y. • Remove the REAR COVER. • Remove the REAR COVER. (1) Disconnect the connectors from the KEY PWB. (1) Disconnect the connectors from the IR PWB.
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REPLACEMENT OF CHIP COMPONENT 3.2.1 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. 3.2.2 SOLDERING IRON (1) Use a high insulation soldering iron with a thin pointed end of it.
SECTION 5 TROUBLESHOOTING Power Turn On Issue Power cannot be turn on (LED does not light) Check if the Power Cord has been well Connect the connector properly connected to AC adapter Is the input voltage DC Change AC adapter Test 12V applied M-PCB again...
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No sound Picture is displayed. But no sound Take off the back cover and check if wires of the speakers terminals have Connect the wires properly been well connected to the PCB-Main and Speakers? Check if the I/P signals Check I/O input circuit applied to I033 audio processor Are there signals on the...
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Key Pad doesn't Work Key pad doesn't work Take off the back cover and check if the wire of PCB-Key Pad has well Connect the wire properly connected to the PCB-Main? Test again Change PCB-Key Pad and connect all wires properly.
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Victor Company of Japan, Limited Display Category 12, 3-chome, Moriya-cho, Kanagawa-ku, Yokohama-city, Kanagawa-prefecture, 221-8528, Japan (No.YA436) Printed in Japan...
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Attention: Europea. If you wish to dispose of this product, please visit our web page www.jvc-europe.com to This symbol is only [Otros países no pertenecientes a la Unión Europea] obtain information about the take-back of the product.
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A nemzeti törvények értelmében az ilyen hulladék helytelen ártalmatlanítása esetén büntetést szabhatnak ki. (Professionelle brugere) Bemærk: Figyelem! Hvis du ønsker at bortskaffe dette produkt, kan du på vores webside www.jvc-europe.com få (Üzleti felhasználók) Dette symbol er kun information om tilbagetagning af produktet. Ez a szimbólum csak gyldigt i EU.
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Warning DO NOT cut off the mains plug from this equipment. If the plug fitted is not suitable for the power points in your home or the cable is too short to reach a power point, then obtain an appropriate safety approved extension lead or adaptor or consult your dealer.
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Thank you for buying this JVC LCD flat television. To make sure you understand how to use your new TV, please read this manual thoroughly before you begin. (“LCD” stands for Liquid Crystal Display.) WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE.
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Point defects LCDs use collections of fine pixels to display images. While there is no problem with more than 99.99% of these pixels, please understand that a very small number of pixels may not light or may light all the time. Distance recommendations Avoid improper installation and never position the unit where good ventilation is impossible.
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Adjust the volume ..........11 Watch images from external equipment ..11 Displaying the source information .....11 ZOOM function..........12 Sleep timer funtion...........13 Picture mode............13 Operating a JVC brand VCR or DVD player ..1 Teletext function........14 Basic operation ..........14 Hold..............14 Sub-page ............14 Reveal..............14 Size ..............15...
Setting up your TV Installation Cautions for installation • Install the TV in a corner on a wall or on the floor so as to keep cords out of the way. • The TV will generate a slight amount of heat during operation. Ensure that sufficient space is available around the TV to allow satisfactory cooling.
Setting up your TV Putting the batteries into the Remote control Use two AA/R6 dry cell batteries. Insert the batteries from the - end, making sure the + and - polarities are correct. • Follow the warnings printed on the batteries. •...
Setting up your TV Connecting the aerial and video Connecting the power cord to the AC cassette recorder (VCR) outlet • The connecting cables are not provided. If you are connecting a AC adapter, follow • For further details, refer to the manuals provided with in the diagram below.
Initial settings When the TV is first turned on, it enters the initial setting 3 AUTO PROGRAM menu appears. mode. Follow the instructions on the on-screen display to make the initial settings. AUTO PROGRAM LANGUAGE ENGLISH COUNTRY UNITED KINGDOM A .P .S VCR/TV/DVD : SELECT :MOVE...
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Initial settings Now, the initial settings are complete, and you can watch the TV • If your TV can detect the TV channel name from the TV channel broadcast signal, the TV channel name is assigned to the programme number to which the TV channel has been set.
TV buttons and functions Turn the TV on from standby mode Press the button or P buttons to turn the TV on from standby mode • Check that the AC plug on the power cord from the TV is connected to correctly AC outlet. Choose a TV channel Press the P buttons to choose a programme...
Remote control buttons and functions 1 Muting bu tton Numbe r buttons 3 Info rma n but 4 ZOOM button buttons (Text) button buttons 10 VCR/DVD/Teletext control buttons buttons 12 Standby button 13 VCR/TV/DVD switch button button Picture button Color buttons MENU button button buttons...
Remote control buttons and functions Displaying the source information Adjust the volume You can display the source information and current time on Press the buttons to adjust the volume. The volume indicator appears and the volume changes as the screen. you press the buttons.
Remote control buttons and functions ZOOM function You can change the screen size according to the picture aspect ratio. Choose the optimum one from the following ZOOM modes. AUTO: The TV automatically chan ges the ZOOM mode to 16:9 mode or 4:3 mode according to the signal from an external device. 4:3: Play a 4:3 image in a 4:3 screen faithfully.
(Standby) button. 2 Press the VCR/DVD Control Button to control your VCR or DVD player • If your device is not made by JVC, these buttons will not work. • Even if your device is made by JVC, some of these buttons may not work, depending on the device you are using.
Teletext function Hold Basic operation You can hold a teletext page on the screen for as long as you want, even while several other teletext pages are being 1 Choose a TV channel with a teletext broadcast received. Press the (Hold) button 2 Make sure to set the VCR/TV/DVD switch to the TV position.
Teletext function Sub-page Cancel Some teletext pages include sub-pages that are You can search for a teletext page while watching TV. automatically displayed. 1 Press the number button to enter a page 1 Choose a teletext page that includes sub-pages number, or press a colour button Press the button, Sub-page numbers can be viewed...
Using the TV’s menu This TV has a number of functions you can operate using 3 Press the buttons to choose a function menus. To use all your TV’s functions, you need to • For details of the functions in the menus, see the understand the basic menu operating techniques fully.
PICTURE SETTING Refer to “Using the TV’s menu” (see page 16) for details of COLOUR TEMP. displaying the menu. You can select one of three COLOUR TEMP. modes (three PICTURE tones of white) to adjust the white balance of the picture. PICTURE MODE BRIGHT Since white is the colour which is used as a reference for all...
SOUND SETTING HYPER SOUND Refer to “Using the TV’s menu” (see page 16) for details of displaying the menu. You can enjoy Surround sound with a “live” effect by using HYPER SOUND function. SOUND BASS function is turned on. HYPER SOUND TREBLE BALANCE OFF:...
FEATURES Refer to “Using the TV’s menu” (see page 16) for details of displaying the menu. FEATURES BLUE BACK CHILD LOCK EXT-2 OUTPUT : SELECT :MOVE BLUE BACK You can set the TV to automatically change to a blue screen and mute the sound if the signal is weak or absent, or when there is no input from an external device.
INSTALL Refer to “Using the TV’s menu” (see page 16) for details of PROGRAM displaying the menu. In TV mode : AUTO PROGRAM INSTALL You can automatically store the TV channels for which you have the best reception. Store them in the TV’s program MANUAL numbers list by doing the following.
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INSTALL NAME After the TV channels have been registered in 1 Press t buttons to choose a TV the programme numbers, the PR LIST menu channel appears • If you want to, you can now edit the program Every time you press the buttons, the numbers using the PROGRAM function.
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INSTALL INSERT 4 Press the green button to insert the channel into 1 Press t buttons to choose a the new program number program number for which you want Every time you press the buttons, the PR LIST programme number changes and the picture of the TV channel stored in the programme number appears 11 ---- 21 ----...
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INSTALL DELETE COLOUR SYSTEM in EXT mode 1 Press t buttons to choose a Press t buttons to choose the colour system program number for which you want When you are in EXT mode, you can only change the Every time you press the buttons, the colour system in the INSTALL menu.
Additional preparation Connecting external equipment Connect the equipment to the TV, making the correct rear 1 VCR (composite signal) panel and front panel connections. 2 VCR (composite signal/S-VIDEO signal) Decoder Before connecting anything: DVD player (composite signal/S-VIDEO signal) • Read the manuals that came with the equipment. DVD player (composite signal/RGB signal) Depending on the equipment, the connection method may be different from the diagram.
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Additional preparation Equipment which can output the S-VIDEO signal (Y/C signal) such as an S-VHS VCR Connect the equipment to an EXT terminal (but not the EXT-1 terminal). You can choose between an S-VIDEO signal (Y/C signal). Connecting headphones Connect the headphones with a stereo mini-jack (3.5 mm diameter) to the headphone socket at the TV.
Troubleshooting If a problem arises while you are using the TV, please read this troubleshooting guide carefully before you ask to have the TV repaired. You may be able to fix it easily by yourself. For example, if the mains plug is disconnected from the mains outlet, or the TV aerial has problems, you may think there is a problem with the TV itself.
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Troubleshooting Other concerns • When the SLEEP TIMER function operates, the TV is automatically turned off. If the TV suddenly turns off, try to press the (standby) button to turn on the TV once again. If the TV goes back to normal, there is no problem.
Specifications Model LT-20C70BU Item Broadcasting systems CCIR B/G, I, D/K, L Colour systems PAL, SECAM • The EXT terminals also support the NTSC 3.58/4.43 MHz system. Channels and frequencies • E2-E12, E21-E69, S1-S41, X, Y, Z, Z+1, Z+2, ITALY A-H, ITALY H+1, ITALY H+2, F2-F10, F21-F69, R1-R12, R21-R69, IR A-J •...
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IR PWB AND KEY PWB CIRCUIT DIAGRAM SHEET 12 MAIN PWB ASS'Y (11/11) MAIN PWB P012 ASS'Y (3/11) (SHEET11) P009 (SHEET3) REMOCON RECEIVER MAIN PWB ASS'Y (3/11) P006 (SHEET3) IR PWB ASS'Y KEY PWB ASS'Y PWB-0997-01.012_0417_12/12_0.0 (No.YA436)2-25 2-26(No.YA436)
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PATTERN DIAGRAMS MAIN PWB PATTERN (No.YA436)2-27 2-28(No.YA436)
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IR PWB AND KEY PWB PATTERN FRONT (No.YA436)2-29 2-30(No.YA436)
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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.YA436) 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 ....................3-3 EXPLODED VIEW PARTS LIST ..........................3-3 EXPLODED VIEW ............................... 3-4 PRINTED WIRING BOARD PARTS LIST ........................3-5 MAIN P.W. BOARD ASS'Y (DA-5098801104) (PWB-0997-A) ................3-5 KEY P.W. BOARD ASS'Y (DA-5098801105) (PWB-0997-B) ................3-9 IR P.W.
SPEAKER SP01 DA-E055109004 SPEAKER SP02 DA-E642024717 RUBBER PAD (x2) DA-G134161182 SCREW M3X8(x6) DA-E642319503 KEY COVER DA-E642850601 DA-E642446700 JVC MARK DA-E642204402 FRONT COVER DA-E640331800 LED LENS DA-E640331900 IR LENS DA-E642204303 MASK DA-E642435300 DC IN LABEL DA-5030409100 SERIAL LABEL DA-E642424800 DECORATED PASTE...
PRINTED WIRING BOARD PARTS LIST MAIN P.W. BOARD ASS'Y Ref No. Part No. Part Name Description Local (DA-5098801104) (PWB-0997-A) Z029 DA-F615002361 Z DIODE 4.85V-5.36V Ref No. Part No. Part Name Description Local Z030 DA-F615002361 Z DIODE 4.85V-5.36V Z031 DA-F615002361 Z DIODE 4.85V-5.36V Z032 DA-F615002361...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C124 DA-E216027903 CAPACITOR 100.0uF 25V M C232 DA-E240633091 CAPACITOR 33.0pF 50V J C125 DA-E216027903 CAPACITOR 100.0uF 25V M C233 DA-E250810591 CAPACITOR 1.0uF 25V Z C126 DA-E216028903 CAPACITOR...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C351 DA-E230003391 CAPACITOR 0.1uF 25V Z R015 DA-E134647209 RESISTOR 1/10W 4.7kΩ J C352 DA-E230003391 CAPACITOR 0.1uF 25V Z R016 DA-E134610309 RESISTOR 1/10W 10.0kΩ J C353 DA-E230003391 CAPACITOR...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local R176 DA-E134600009 RESISTOR 1/10W 0.0Ω J R368 DA-E134651009 RESISTOR 1/10W 51.0Ω J R177 DA-E134610209 RESISTOR 1/10W 1.0kΩ J R375 DA-E134633009 RESISTOR 1/10W 33.0Ω J R178 DA-E134647209 RESISTOR...
PACKING PACKING PARTS LIST Ref.No. Part No. Part Name Description Local DA-I513530556 CARTON BOX DA-I523530156 CUSHION (L) DA-I523530256 CUSHION (R) DA-I533399956 POLY BAG (x2) DA-I533399856 POLY BAG DA-E056706169 POWER CORD DA-E061370334 AC/DC ADAPTER DA-I533251257 POLY BAG DA-E030057219 INST BOOK DA-I533252157 POLY BAG...