COLOUR TELEVISION YA252 2005 AV-21U4 BASIC CHASSIS TABLE OF CONTENTS PRECAUTION............... . . 1-3 SPECIFIC SERVICE INSTRUCTIONS .
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SPECIFICATION Items Contents Dimensions (W × H × D) 50.3cm × 46.7cm × 48.0cm Mass 20kg TV RF System B, G, I, D, K Colour System TV Mode PAL / SECAM Video Mode PAL / SECAM / NTSC3.58 / NTSC4.43 Receiving Frequency VHF Low 46.25MHz ~ 140.25MHz (AS0 ~ S6)
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 input terminals. •...
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MAIN CPU [MAIN PWB : IC701] PIN FUNCTION Pin name Function Pin name Function 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 VrefP_Sdac 3.3V (Positive)
SECTION 3 DISASSEMBLY DISASSEMBLY PROCEDURE 3.1.1 REMOVING THE REAR COVER • Unplug the power cord. (1) Remove the 5 screws [A] and 2 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 CRT SOCKET PWB SPEAKER MAIN PWB REAR COVER Fig.1 (No.YA252)1-7...
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REPLACEMENT OF MEMORY IC 3.2.1 MEMORY IC This TV uses the following memory IC. SERVICE MENU Memory IC: IC702 on MAIN PWB The memory IC memorizes data for correctly operating the video SERVICE MENU and deflection circuits. When replacing the memory IC, be sure 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 MULTI TRIPLE THAI SYSTEM TRIPLE COMB TILT SUPER BASS SINGLE TEXT E/R/C/M/I LANGUAGE E/R/C/M/I STEREO MONO SOUND MONO BILINGUAL BLUE BACK MUTE COLOUR AUTO ECO SENSOR SURROUND PICTURE BOOSTER COMPONENT...
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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 DATA VOLUME 2. CUTOFF(B/G) COLOR SYSTEM 3. WDR(R/G/B) 4. BRIGHT(TV/VDO 1/2) SOUND SYSTEM 5.
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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) 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.
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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.
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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).
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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. •...
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Measuring Item Test point Adjustment part Description instrument WHITE Signal [2. V/C] Note: BALANCE generator 2. CUTOFF (B) • Set PICTURE MODE (VSM) to "BRIGHT". (Low light) 2. CUTOFF (G) (1) Receive a PAL black and white signal (colour off). adjustment Remote (2) Select 2.
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Measuring Item Test point Adjustment part Description instrument SUB BRIGHT Remote [2. V/C] Notes: adjustment control unit 4. BRIGHT • Proceed to the following adjustment after having completed the WHITE BALANCE (Low light) and WHITE BALANCE (High light) adjustment. • Set PICTURE MODE (VSM) to "BRIGHT". (1) Receive a broadcast.
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Measuring Item Test point Adjustment part Description instrument SUB COLOUR 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. •...
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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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4.7.5 DEFLECTION 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. •...
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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 H. BOW Signal [4.DEF] - PAL H. BOW - adjustment generator 11. BOW (1) Receive a PAL crosshatch signal. (2) Select 11. BOW. Remote (3) Set the initial setting value of 11. BOW. control unit (4) Adjust 11.
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.YA252) Printed in Japan...
AV-21U4 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.
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-21U4/SK MAIN P.W. BOARD SCW-1398A-H2 CRT SOCKET P.W. BOARD SCW-3013A-H2 2-2(No.YA252)
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BLOCK DIAGRAM MAIN PWB IC701 MAIN MICRO COMPUTER/ IC351 IF . VIDEO . RGB . SYNC . DEF. PROCESS RGB OUT CRT SOCKET 108,109 SCL1, SDA1 I 2 C IC702 127,128 SCL0, SDA0 MICRO MAIN MEMORY DIGITAL SIGNAL PROCESS COMPUTER TU001 98,99 PW_LED...
K107 10/50 Y105 QUY160-150Y K104 Y106 Y822 QQR1114-001Z K105 SCW-1398A-H2 [AV-21U4/SK] QUY160-150Y QUY160-150Y K106 Y107 Y824 QUY160-150Y QUY160-200Y NOTE) 1.Refer to the part list for the part number of IC701 and IC702. 2.Refer to page 2-13 for voltages of this circuit diagram.
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QUY160-050Y L522 R528 C530 Y581 QUY160-100Y Y582 MAIN PWB ASS'Y (2/2) SCW-1398A-H2 [AV-21U4/SK] CN0HV QGZ5004C1-04 NOTE) 1.Refer to page 2-13 for voltages of this circuit diagram. 2.Refer to page 2-14 for waveforms of this circuit diagram. DEF YOKE (No.YA252)2-7 2-8(No.YA252)
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VOLTAGE CHARTS WAVEFORMS <MAIN PWB> <CRT SOCKET PWB> -MAIN PWB- MODE MODE MODE MODE DC (V) DC (V) DC (V) DC (V) PIN NO. PIN NO. PIN NO. PIN NO. IC401 IC351 IC401-1 IC401-3 IC401-5 IC401-6 25.7 Q101 13.0 11.6 26.0 185.7 Q521...
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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.YA252) Printed in Japan...
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-21U4/SK MAIN P.W.B SCW-1398A-H2 CRT SOCKET P.W.B SCW-3013A-H2 REMOTE CONTROL UNIT RM-C1261-2H EXPLODED VIEW PARTS LIST -1 Ref.No. Part No. Part Name Description Local LC10156-006A-HK FRONT CABINET CM47783-003-H JVC MARK...
EXPLODED VIEW PARTS LIST -2 Ref.No. Part No. Part Name Description Local V01 A51KQK99X01 PICTURE TUBE(ITC) Inc.DEF YOKE,PC MAGNET L01 QQW0077-001 DEG COIL T522 QQH0170-001 FB TRANSF QYSBSFG4016ZA TAP SCREW M4 x 16mm(x5) QYSBSF3010ZA TAP SCREW M3 x 10mm(x2) LC10157-004A-HK REAR COVER...
PRINTED WIRING BOARD PARTS LIST MAIN P.W. BOARD ASS'Y (SCW-1398A-H2) Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local D928 MTZJ16C-T2 Z DIODE D929 1SS133-T2 SI DIODE IC401 LA78040N D931 MTZJ9.1C-T2 Z DIODE IC601 AN5279 D932...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local C720 NCB31HK-102X C CAPACITOR 1000pF 50V K C962 NCB31CK-104X C CAPACITOR 0.1uF 16V K C721 QETN1CM-476Z E CAPACITOR 47uF 16V M C963 NCB31HK-102X C CAPACITOR 1000pF 50V K C723 NCB21CK-105X...
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Ref No. Part No. Part Name Description Local Ref No. Part No. Part Name Description Local R609 NRSA63J-273X MG RESISTOR 27kΩ 1/16W J R798 NRSA63J-103X MG RESISTOR 10kΩ 1/16W J R610 NRSA63J-104X MG RESISTOR 100kΩ 1/16W J R801 NRSA63J-750X MG RESISTOR 75Ω...
PACKING PACKING PARTS LIST Ref.No. Part No. Part Name Description Local GG10281-008A-H PACKING CASE LC10158-005B-H CUSHION ASSY 4pcs in 1set GG30097-003A-H POLY BAG GG30096-001A-H POLY BAG ------------ BATTERY AA/R6(x2) GGT0047-001C-H INST BOOK BT-54012-4H WARRANTY CARD RM-C1261-2H REMOCON UNIT GG20025-005A-H CORNER LABEL (x2)