SERVICE MANUAL FLAT COLOR TELEVISION YA255 2005 AV-25VT15 BASIC CHASSIS TABLE OF CONTENTS PRECAUTION............... . . 1-3 SPECIFIC SERVICE INSTRUCTIONS .
SPECIFICATION Items Contents Dimensions (W × H × D) 72.8cm × 53.6cm × 48.15cm Mass 33kg TV RF System M / N Color System TV Mode NTSC / PAL-M / PAL-N Video Mode NTSC / PAL-M / PAL-N Stereo System MTS (Multi-Channel Television Sound) Receiving Frequency VHF Low...
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.
SECTION 2 SPECIFIC SERVICE INSTRUCTIONS FEATURES • New chassis design enables use of an interactive on-screen control. • Pure flat CRT produces fine textured picture in every detail. • Wide range voltage (110V ~ 240V) for AC power input. • With AUDIO/VIDEO/S-VIDEO/COMPONENT input terminals. •...
FRONT PANEL CONTROLS POWER MENU HEADPHONE jack VOLUME (-/+) buttons IN (VIDEO-3) : VIDEO Remote control sensor IN (VIDEO-3) : AUDIO L/MONO ECO sensor IN (VIDEO-3) : AUDIO R POWER lamp MENU (OK) button MAIN POWER button CHANNEL (-/+) buttons REAR TERMINAL VIDEO-1 INPUT TERMINAL S-VIDEO...
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MAIN CPU [MAIN PWB : IC701] PIN FUNCTION Pin no. Pin name Remark Pin no. Pin name Remark CVBSO/PIP O CVBS / PIP output VssP2 O Scan velocity modulation output VssC4 FbiSo Flyback input/sandcastle output V1.8C4 1.8V (Digital) Hout O Horizontal output V3.3A3 3.3V VssComb...
SECTION 3 DISASSEMBLY DISASSEMBLY PROCEDURE 3.1.1 REMOVING THE REAR COVER • Unplug the power cord. (1) Remove the 11 screws [A] and 4 screws [B] as shown in Fig.1. (2) Withdraw the REAR COVER toward you. CAUTION: When reinstalling the rear cover, carefully push it inward after inserting the MAIN PWB into the REAR COVER groove.
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FRONT CABINET PICTURE TUBE (x2) SPEAKER MAIN PWB (CRT SOCKET PWB) MAIN PWB (x2) SPEAKER REAR COVER (x11) (x4) Fig.1 1-8 (No.YA255)
REPLACEMENT OF MEMORY IC 3.2.1 MEMORY IC This TV uses the following memory IC. Memory IC: IC702 on MAIN PWB SERVICE MENU The memory IC memorizes data for correctly operating the video and deflection circuits. When replacing the memory IC, be sure SERVICE MENU to use the same type IC written with the initial values of data.
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3.2.3 FACTORY SETTING VALUE SETTING OF SYSTEM CONSTANT SET Setting item Setting content Setting value TAIWAN OTHERS SYSTEM OTHERS COMB TILT SUPER BASS STEREO MONO SOUND STEREO BLUE BACK MUTE ECO SENSOR SURROUND PICTURE BOOSTER COMPONENT S INPUT Table 1 1-10 (No.YA255)
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SETTING OF BASIC FUNCTIONS SERVICE MENU SETTING ITEMS Setting item Setting value Setting item Setting value POWER 1. IF 1. VCO 2. DELAY POINT SUB POWER 2. V/C 1. SCREEN VOLUME 2. CUTOFF(B/G) COLOR SYSTEM PAL-N 3. WDR(R/G/B) 4. BRIGHT(TV/VDO 1/2/3) PICTURE MODE (VSM) BRIGHT 5.
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) You can make the necessary adjustments for this unit with either the remote control unit or with the adjustment equipment and parts as given below. (2) Adjustment with the remote control unit is made on the basis of the initial setting values, however, the new setting values used for setting the screen to its optimum condition may differ from the initial settings.
BASIC OPERATION IN SERVICE MENU Operate the SERVICE MENU with the remote control unit. 4.6.1 SERVICE MENU ITEMS With the SERVICE MENU, various settings (adjustments) can be made, and they are broadly classified in the following items of settings: 1. IF For entering/adjusting the setting values (adjustment values) of the IF circuit.
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4.6.3 SERVICE MENU FLOW CHART 1. IF SERVICE MENU SERVICE MENU IF SERVICE MENU 1. IF 2. V/C VCO (CW) ***** 3. AUDIO 4. DEF TOO HIGH 5. VSM W/B 6. STATUS 1. VCO ABOVE REFERENCE 7. PLUG & PLAY (ON) JUST REFERENCE 2.
ADJUSTMENT PROCEDURE 4.7.1 B1 VOLTAGE Measuring Item Test point Adjustment part Description instrument B1 VOLTAGE Signal B1 (pin 1) (1) Receive a black and white signal. check generator GND (pin 5) (2) Connect a DC voltmeter between B1 and GND [CN00X (between pins 1 and 5 of the connector CN00X).
4.7.4 VIDEO CIRCUIT ADJUSTMENTS • 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. •...
Measuring Item Test point Adjustment part Description instrument WHITE Signal [2. V/C] Notes: BALANCE generator 3. WDR (R) • Proceed to the following adjustment after having (High light) 3. WDR (G) completed the WHITE BALANCE (Low light) adjustment. adjustment Remote 3.
Measuring Item Test point Adjustment part Description instrument SUB COLOR 1 Remote [2. V/C] [Method of adjustment without measuring instrument] adjustment control unit 6. COLOUR Notes: • Proceed to the following adjustment after having completed the SUB CONTRAST adjustment. • Set PICTURE MODE (VSM) to "BRIGHT". - PAL-M COLOR - (1) Receive a PAL-M broadcast.
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Measuring Item Test point Adjustment part Description instrument SUB COLOR 2 Signal TP-47G [2. V/C] [Method of adjustment using measuring instrument] adjustment generator TP-E 6. COLOUR Notes: [CRT SOCKET • Proceed to the following adjustment after having Oscilloscope PWB] completed the SUB CONTRAST adjustment. •...
Measuring Item Test point Adjustment part Description instrument SUB TINT 2 Signal TP-47G [2. V/C] [Method of adjustment using measuring instrument] adjustment generator TP-E 7. TINT Notes: [CRT SOCKET • Proceed to the following adjustment after having Oscilloscope PWB] completed the SUB CONTRAST adjustment. •...
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COMPRESS: OFF (4:3) Measuring Item Test point Adjustment part Description instrument V. SLOPE Signal [4. DEF] - PAL V. SLOPE - adjustment generator 2. V-SLOPE (1) Receive a PAL circle pattern signal of vertical frequency 50Hz. Remote (2) Select 4. DEF from the SERVICE MENU. control unit (3) Select 2.
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Measuring Item Test point Adjustment part Description instrument H. POSITION Signal [4. DEF] - PAL H. POSITION - adjustment generator 4. H-CENT (1) Receive a PAL circle pattern signal. (2) Select 4. H-CENT. Remote (3) Set the initial setting value of 4. H-CENT. control unit (4) Adjust 4.
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Measuring Item Test point Adjustment part Description instrument TRAPEZIUM Signal [4.DEF] - PAL TRAPEZIUM - adjustment generator 6. TRAPEZ (1) Receive a PAL crosshatch signal. (2) Select 6. TRAPEZ. Remote (3) Set the initial setting value of 6. TRAPEZ. control unit (4) Adjust 6.
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Measuring Item Test point Adjustment part Description instrument H. PARALLEL Signal [4.DEF] - PAL H. PARALLEL - adjustment generator 10. ANGLE (1) Receive a PAL crosshatch signal. (2) Select 10. ANGLE. Remote (3) Set the initial setting value of 10. ANGLE. control unit (4) Adjust 10.
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COMPRESS : ON (16:9) Measuring Item Test point Adjustment part Description instrument V. HEIGHT Signal [4.DEF] - PAL V. HEIGHT - adjustment generator 14. V. ZOOM (1) Receive a PAL crosshatch signal of vertical 3. V-SIZE frequency 50Hz. Remote (2) Press the [MENU] key and select PICTURE. control unit (3) Select PICTURE FEATURES.
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Measuring Item Test point Adjustment part Description instrument SIDE PIN Signal [4. DEF] - PAL SIDE PIN - adjustment generator 7. EW-PIN (1) Receive a PAL crosshatch signal. (2) Select 7. EW-PIN. Remote (3) Set the initial setting value of 7. EW-PIN. control unit (4) Adjust 7.
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VIDEO - 2 SET: COMPONENT Measuring Item Test point Adjustment part Description instrument H. POSITION Signal [4. DEF] (1) Receive a PAL circle pattern signal to VIDEO-2 adjustment generator 4. H-CENT component terminal. (2) Select VIDEO-2 SET from the MENU and set Remote VIDEO-2 SET to COMPONENT.
4.7.8 CONVERGENCE STATIC CONVERGENCE ADJUSTMENT (1) Input a crosshatch signal. (2) Using 4-pole convergence magnets, overlap the red and blue lines in the center of the screen (Fig.1) and turn them (FRONT VIEW) to magenta (red/blue). (3) Using 6-pole convergence magnets, overlap the magenta (red/blue) and green lines in the center of the screen and turn them to white.
SECTION 5 TROUBLESHOOTING SELF CHECK FUNCTIONS 5.1.1 OUTLINE This model has self check functions given below. When an abnormality has been detected, the SUB POWER is turned off and POWER LED flashes to inform of the failure. An abnormality is detected by the signal input state of the control line connected to the microcomputer.
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Victor Company of Japan, Limited AV & MULTIMEDIA COMPANY VIDEO DISPLAY CATEGORY 12, 3-chome, Moriya-cho, kanagawa-ku, Yokohama, kanagawa-prefecture, 221-8528, Japan (No.YA255) Printed in Japan...
AV-25VT15 STANDARD CIRCUIT DIAGRAM NOTE ON USING CIRCUIT DIAGRAMS 1.SAFETY Type No indication : Ceramic capacitor The components identified by the symbol and shading are : Metalized mylar capacitor critical for safety. For continued safety replace safety ciritical : Polypropylene capacitor components only with manufactures recommended parts.
TOP VIEW CHIP TR E C B E C B ( G ) ( D ) ( S ) BOTTOM VIEW FRONT VIEW TOP VIEW CHIP IC TOP VIEW USING P.W.BOARD P.W. BOARD ASS'Y NAME AV-25VT15/R MAIN P.W. BOARD SCW-1141A-CK 2-2(No.YA255)
BLOCK DIAGRAM MAIN PWB IC701 MAIN MICRO COMPUTER/ IF VIDEO RGB SYNC DEF. PROCESS IC351 108,109 SCL1, SDA1 RGB OUT I 2 C IC702 127,128 SCL0, SDA0 MICRO MAIN MEMORY DIGITAL SIGNAL PROCESS COMPUTER TU001 98,99 TUNER REMOTE PORT KEY_IN CRT SOCKET PEAKING SCAN ROUT...
VOLTAGE CHARTS <MAIN PWB> <MAIN PWB (CRT SODKET)> MODE MODE MODE MODE MODE DC ( V ) DC ( V ) DC ( V ) DC ( V ) DC ( V ) PIN NO. PIN NO. PIN NO. PIN NO. PIN NO.
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Victor Company of Japan, Limited AV & MULTIMEDIA COMPANY VIDEO DISPLAY CATEGORY 12, 3-chome, Moriya-cho, kanagawa-ku, Yokohama, kanagawa-prefecture, 221-8528, Japan (No.YA255) Printed in Japan...
COLOR TELEVISION EQUALIZER • CINEMA SURROUND • COMPONENT INPUT Contents AV-29VT15 AV-21VT15 Knowing your TV’s features ............3 Remote control buttons and basic functions ......4 AV-29VT35 TV buttons and functions ............6 Setting up your TV ..............7 AV-25VT15 Basic setting for picture ..............
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Thank you for buying this JVC color television. To make sure you understand how to use your new TV, please read this manual thoroughly before you begin. WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT 7 If you are not going to use this TV for a long period of time, be sure to EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE.
Knowing your TV’s features Main features You can listen to the stereo sound or SAP from TV program broadcasting by MTS system. (SAP: Second audio program.) CLOSED CAPTION You can display dialog on the screen from TV broadcasting with Closed Caption system. You may also be able to display some information in text form if available.
Remote control buttons and basic functions No. Press POWER Turn on or off the TV from standby mode. MENU/OK Display menu and confirm selected function. 5 / ∞ / 2 / 3 Select and adjust menu function. CHANNEL -/+ Select the desired channel number. VOLUME -/+ Adjust the volume level.
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Remote control buttons and basic functions (continued) How to operate menus and menus locations Top menu 2nd menu Location 3rd menu Location MENU INPUT EXT. INPUT P.16 – – Operation Note DISPLAY P.16 – – Press the MENU/OK button 2. Display the MENU To exit the MENU, CLOSED CAPTION P.15...
TV buttons and functions The illustrations shown below is for AV-29VT35 only, No. Button/terminal Description Page which are used for explanation purpose. L (main power) Press to turn on or turn off the TV’s main power. – Your TV may not look exactly the same as illustrated. POWER lamp Indicate the TV is being turned on or off.
COMPONENT VIDEO-1 (VIDEO-2) OUTPUT INPUT INPUT Turn on the TV by pressing the main power button. OVER JVC logo appears on the screen. / MONO MONO To video To audio To RF output output output To S-video...
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SETUP TOUR RESTART function. If the JVC logo does not appear, use AUTO PROGRAM function to make the initial settings. This function is located in the INSTALL menu. If the JVC logo appears, although you had made the initial settings, press the TV/VIDEO button to exit from initial settings.
Basic setting for picture COLOR SYSTEM PICTURE MODE You can select the appropriate color system when the picture is You can choose the desired picture setting with one-touch. not clear or no color appears. Press the PICTURE MODE button to select a setting. Press the COLOR SYSTEM button to select a setting.
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Basic setting for picture (continued) Adjusting the picture – USER WHITE BALANCE You can adjust the desired picture setting when selecting USER You can change the white balance of the picture to better match in PICTURE MODE. the type of video being viewed. Select the WHITE BALANCE in the PICTURE menu, then choose Select the USER in PICTURE MODE under PICTURE menu.
Advanced setting for picture Press the 5/∞ buttons until the picture become level. Then AI ECO SENSOR (ECO) press the MENU/OK button. You can adjust TV screen contrast according to the brightness of your room. Press the ECO button to select the desired mode. COMPRESS (16:9) Mild contrast (recommended).
Basic setting for sound BALANCE SUPER BASS (BASS) You can adjust the volume balance between the left and right You can enjoy powerful bass sound with the Twin Port Bass speakers. Blaster unit. Select the BALANCE in SOUND menu, then adjust the setting. Press the BASS button to select ON or OFF.
Advanced setting for sound CINEMA SURROUND EQUALIZER You can enjoy an enhanced sound for wider audience. You can adjust the sound level of each frequencies when selecting Press the CINEMA SURROUND button to select a setting. USER mode in SOUND MODE. Select the USER in SOUND MODE under SOUND menu.
Favorite channel and video setting To register the favorite channel Select the desired item that you wish to adjust. PICTURE BRIGHT DETAIL COLOR You can register and recall 4 favorite channels by using the color buttons (red, green, yellow, blue). SOUND MODE (USER, DYNAMIC, MUSIC, NEWS) TINT* *TINT can only be adjusted in NTSC signal.
Customized setting CHILD LOCK You can reduce the picture noise. You can disable the front control buttons of the TV. Select the VNR in the PICTURE FEATURES menu under Select the CHILD LOCK in the FEATURES menu, then choose PICTURE menu, then choose a setting of VNR function. ON or OFF.
Customized setting (continued) AUTO SHUTOFF EXT. INPUT (TV/VIDEO) You can set the TV to turn off automatically when no signal is You can select TV or video terminal input with one touch. received for about 15 minutes or longer after the end of a Press the TV/VIDEO button to select an input.
TV channel presetting Choose CHANNEL SUMMARY, then press the MENU/OK To register the TV channels automatically button. You can register the TV channels into the TV’s channel list CHANNEL SUMMARY menu appears. automatically. Display the INSTALL menu. CHANNEL SUMMARY ❇ CH/CC SKIP INSTALL menu...
Additional preparation The illustrations shown in this section are for AV-29VT35 and AV- Connecting to rear component/video input 21YT15 only, which are used for explanation purpose. Your TV terminal and output terminal may not look exactly the same as illustrated. Rear of TV AV-29VT35 Before connecting...
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Additional preparation (continued) CAUTION: Attaching the Twin Port Bass Blaster Unit The Twin Port Bass Blaster Unit is just placed on top of the TV <AV-29VT35 only> and is not held in place by a screw. When using the unit, pay The Twin Port Bass Blaster Unit is packaged together with the attention to the following cautions.
Troubleshooting If a problem occurs when you are using the TV, check the below • Cannot operate the • The batteries may be exhausted. Replace with troubleshooting guide before calling for repair. remote control new batteries (see page 7). • Ensure that you are operating the remote less than seven meters from the front of your TV.
Specifications TV RF systems M, N Color systems NTSC, PAL-M, PAL-N Receiving channels VHF low channel (VL), VHF high channel (VH), UHF channel (U) Receives cable channels in mid band, super band and hyper band. External input / output VIDEO-1: S-video input, VIDEO input, AUDIO L/R input VIDEO-2/COMPONENT: VIDEO input, AUDIO L/R input, COMPONENT VIDEO (Y/C ) input...
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 -1 ..........................3-3 EXPLODED VIEW -1 ..............................3-3 EXPLODED VIEW PARTS LIST -2 ..........................3-4 EXPLODED VIEW -2 ..............................3-5 PRINTED WIRING BOARD PARTS LIST ........................3-6 MAIN P.W.
USING P.W. BOARD & REMOTE CONTROL UNIT P.W.B ASS'Y AV-25VT15/R MAIN P.W.B SCW-1141A-CK REMOTE CONTROL UNIT RM-C1288-1H EXPLODED VIEW PARTS LIST -1 Ref.No. Part No. Part Name Description Local GG30068-001A-H AV SHEET GG40023-003A-H JVC MARK GG30044-001B-H REMOCON LENS GG30042-001B-H LED LENS ...
EXPLODED VIEW PARTS LIST -2 Ref.No. Part No. Part Name Description Local V01 A59QDC580X09TD PICTURE TUBE Inc.DEF YOKE,PC MAGNET L01 QQW0119-001 DEG COIL T522 QQH0187-001 FB TRANSF QYSBSFG4016ZA TAP SCREW M4 x 16mm(x11) QYSBSF3010ZA TAP SCREW M3 x 10mm(x4) GG10249-007A-HK REAR COVER...
PRINTED WIRING BOARD PARTS LIST MAIN P.W. BOARD ASS'Y (SCW-1141A-CK) Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local D708 MA111-X SI DIODE D709 MA111-X SI DIODE IC302 S9066-11 PHOTO CONDUCTOR D710 MA8091/H/-X Z DIODE IC351 TDA6107AJF/N1...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C522 QFLC1HJ-223Z M CAPACITOR 0.022uF 50V J C753 NCB31HK-104X C CAPACITOR 0.1uF 50V K C523 QETN1VM-476Z E CAPACITOR 47uF 35V M C754 NCB31HK-104X C CAPACITOR 0.1uF 50V K C524 QFZ0196-252...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C989 NCB31HK-104X C CAPACITOR 0.1uF 50V K R575 NRSA63J-222X MG RESISTOR 2.2kΩ 1/16W J QCZ9079-102 C CAPACITOR 1000pF AC250V M R581 QRE121J-822Y C RESISTOR 8.2kΩ...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local R772 NRSA63J-222X MG RESISTOR 2.2kΩ 1/16W J L708 NQL092K-100X COIL 10uH K R773 NRSA63J-392X MG RESISTOR 3.9kΩ 1/16W J L709 NQL092K-100X COIL 10uH K R774 NRSA63J-222X MG RESISTOR...
REMOTE CONTROL UNIT PARTS LIST (RM-C1288-1H) Ref No. Part No. Part Name Description Local R25-8566 BATTERY COVER PACKING PACKING PARTS LIST Ref.No. Part No. Part Name Description Local GG10359-003A-D PACKING CASE GG10252-003A-D CUSHION ASS'Y 4pcs in 1set GG30124-004A-D POLY BAG GG30123-001A-D POLY BAG INST.
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