21LT-45S SERVICE MANUAL SE0021LT45S00 Issued: 16th Feb. 2004 AK- 44 CHASSIS PAL B/G / SECAM L/L’, B/G, D/K SYSTEM COLOUR TELEVISION MODEL 21LT-45SES In the interests of user safety (required by safety regulations in some countries) the set should be restored to its original condition and only parts identical to those specified should be used. In order to service the model 21LT-45S, refer to the AK-44 Chassis Service Manual (SE00AK44CHA00). CONTENTS ELECTRICAL SPECIFICATIONS ..........................
1LT-45S SERVICE MANUAL UPDATE LOG SHEET Technical Report No. Technical Bulletin No. Cause / Solution Part No. Page No. Application Data /Serial No. Use this page to keep any special servicing information as Technical Report (Bulletin), Technical Information, etc. If only part number changes are required, just change part number directly the part number in the Parts Listing Section. If you need more information, please refer to the Technical Report (Bulletin).
21LT-45S ELECTRICAL SPECIFICATIONS •Picture Intermediate frequency L’ ................................................ 33.9MHz L, B/G, D/K .............................. 38.9MHz •Power Input .................... 220V-240 Volts AC 50 Hz •Power Consumption Normal Operation (Method IEC60107) .............. 60 W Stand-by Operation .......................................... < 3 W •Sound Carrier Trap L’ ................................................ 40.4MHz L, D/K .........................................
21LT-45S IMPORTANT SERVICING NOTES Only qualified service personnel are allowed to carry out maintenance and repair of this receiver. Servicing of High Voltage System and CRT It is important that the static charge is removed from the high voltage system when carrying out work on the receiver. This can be achieved by connecting a 10K resistor (with a suitably insulated lead) from the CRT cavity connector to the CRT ground tag. This must be carried out with the AC supply disconnected from the receiver.
21LT-45S CONTROLS & TERMINALS Speaker ( right) = Power On / Off = Volume -/+ CH = Program -/+ MENU = Menu REMOTE CONTROL 1 2 3 4 5 6 7 8 9 10 = Stand By = Cursor Up = Cursor Right OK = OK = Info (Program Menu) 0 - 9 = Direct Program -/-- = Double Digit = Wide mode button P/CH+ = Program + + = Volume + 11 12 = TV / Quit Menu = EXT button (SCART, F- AV, RGB) 13 Yellow = Feature Menu 14 Blue = Installation Menu EXT 15 = Hold 16 = Update 17 = Index Page 18 = Reveal 19 = Expand 20 = Mix 21 = Teletext 22
21LT-45S CHASSIS LAYOUT Mother Unit CRT Unit 6
21LT-45S 21LT-45S PARTS LISTING REPLACEMENT PARTS Replacement parts which have special safety characteristics are identified in this manual. Electrical components having such features are identified by in the Replacement Parts Listing. The use of a substitute replacement part which does not have the same safety characteristics as the factory recommended is not permitted. Replacement parts not shown in this service manual may create shock fire, or other hazards.
21LT-45S ! ! ! ! ! REF No.
21LT-45S 21LT-45SES PARTS LISTING REPLACEMENT PARTS Replacement parts which have special safety characteristics are identified in this manual. Electrical components having such features are identified by in the Replacement Parts Listing. The use of a substitute replacement part which does not have the same safety characteristics as the factory recommended is not permitted. Replacement parts not shown in this service manual may create shock fire, or other hazards.
21LT-45S ! ! ! ! ! REF No.
21LT-45S How to update the Technical Information appeared on this Service Manual 1. Web site: https://www.vestelservice.com 2. Select: Technical Support 3. Login: 101278 4. Password: SHPII278 By this access you can consult the latest schematic diagram or request the Parts Listing of a concrete Production Date / Serial Number. By this way it can be also consulted the issued Technical Reports (Service Bulletins).
21LT-45S No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher. Technical information and Production: Vestel Electronik AS PRINTED BY: ON: Think Ecology, please use Technical information re-issued: SHARP ELECTRONICA ESPAÑA S.A. Service Manual Group Engineering Dept.
AK - 44 CHASSIS SERVICE MANUAL SE00AK44CHA00 Issued: 9th March 2004 PAL B/G, I / SECAM L/L’, B/G, D/K SYSTEM COLOUR TELEVISION CHASSIS AK-44 In the interests of user safety (required by safety regulations in some countries) the set should be restored to its original condition and only parts identical to those specified should be used. CONTENTS TABLE OF CONTENTS ....................................................................................................... 3 INTRODUCTION .......................
AK - 44 CHASSIS SERVICE MANUAL UPDATE LOG SHEET Technical Report No. Technical Bulletin No. Cause / Solution Part No. Page No. Application Data /Serial No. Use this page to keep any special servicing information as Technical Report (Bulletin), Technical Information, etc. If only part number changes are required, just change part number directly the part number in the Parts Listing Section. If you need more information, please refer to the Technical Report (Bulletin).
AK - 44 CHASSIS TABLE OF CONTENTS SAFETY PRECAUTIONS ............................................................................................................................................... 5 TV set switched off ............................................................................................................................................... .....5 Measurements ................................................................................................................................
AK - 44 CHASSIS TDA1308 ................................................................................................................................................................ 21 SAW FILTERS ....................................................................................................................................................... 21 13. GENERAL BLOCK DIAGRAM of 11AK44 ..................................................................................................................22 14.
AK - 44 CHASSIS SAFETY PRECAUTIONS The service of this TV set must be carried out by qualified persons only. Components marked with the warning symbol on the circuit diagram or on the Parts Listing, are critical for safety and must only be replaced with an identical component. - Power resistor and fused resistors must be mounted in an identical manner to the original component. - When servicing this TV, check that the EHT does not exceed 26kV.
AK - 44 CHASSIS 1. INTRODUCTION 11AK44 is a 90° chassis capable of driving 20"/21" tubes at the appropriate currents. The chassis is capable of operating in PAL, SECAM and NTSC standards. The sound system is capable of giving 4 watts RMS output into a load of 16 ohms. 7 page SIMPLETEXT is provided. The chassis is equipped with a single-deck 21 pin Scart connector. CIRCUIT DESCRIPTIONS 2.
AK - 44 CHASSIS composed of an integrated VCO (12 MHz) that requires the chroma Reference frequency (4.43 MHz or 3.58 MHz crystal oscillator reference signal), a divider by 768, a line decoder, and a phase comparator. • PLL2: The second phase locked loop that controls the phase of the horizontal output (Compensation of horizontal deflection transistor storage time variation). Also the horizontal position adjustment is also performed in PLL2. • A vertical pulse extractor.
AK - 44 CHASSIS 2.9 µ-Controller The ST92195 is the micro-controller, which is required for a color TV receiver. ST92195D1 is the version with one page Teletext and ST92195D7 is the one with 7 page Teletext. The IC has the supply voltage of 5 V and they are mounted in PSDIP package with 56 pins.
AK - 44 CHASSIS 2.10 Video Path The detected video signal is output from pins 18 of IC403, to sound traps Z403/404. The video is taken from the other side via the appropriate filter to Pin 18 of IC403. (1.2 p to p) Video to the Scart connectors is taken after R458 to Pin 19 of the Scart connector. The CVBS_TXT output Pin29 output is fed to IC501 Pin 34 (for Teletext). The video signal is sometimes labelled CVBS on the circuit diagram. This stands for Composite Video Blanking & Sync.
AK - 44 CHASSIS (2). Enough margin is available to tune up to 863.25 MHz. Noise Low band: Mid band: High band: Typical 5 dB 5dB 6 dB Max. 9 dB 9 dB 9 dB Gain All channels: Gain Taper (of-air channels): Min. 38 dB Typical 44 dB Max. 52 dB 8 dB Channel Coverage UV1336 BAND CHANNELS FREQUENCY RANGE (MHz) Low Band Mid Band High Band 2 to D E to PP QQ to 69 55.25 to 139.25 145.25 to 391.25 397.25 to 801.25 Noise is typically 6 dB for all channels.
AK - 44 CHASSIS 7. VIDEO OUTPUT AMPLIFIER TDA6107JF/N3 The TDA6107JF includes three video output amplifiers and is intended to drive the three cathodes of a colour CRT directly. The device is contained in a plastic DIL-bent-SIL 9-pin medium power (DBS9MPF) package, and uses highvoltage DMOS technology. To obtain maximum performance, the amplifier should be used with black-current control. 8.
AK - 44 CHASSIS This Current Sense pin senses the voltage developed on the series resistor R806 inserted in the source of the power MOSFET. When I sense reaches 1V, the Driver output (pin 5) is disabled. This is known as the Over Current Protection function. A 200mA current source is flowing out of the pin 3 during the start–up phase and during the switching phase in case of the Pulsed Mode of operation.
AK - 44 CHASSIS 9.1 B.C.L Circuit (Beam Current Limiter) Beam current limiting is employed to protect the circuitry in the receiver, the CRT and to prevent excessive X Ray radiation in fault conditions. The current drawn by the CRT is monitored by the current drawn through the winding of the fly-back transformer that produces the EHT for the CRT anode.
AK - 44 CHASSIS ST92195 The ST92195 is a member of the ST9+ family of micro-controllers, completely developed and produced by STMicroelectronics using a proprietary n-well HCMOS process. The nucleus of the ST92195 is the advanced Core, which includes the Central Processing Unit (CPU), the ALU, the Register File and the interrupt controller. The Core has independent memory and register buses to add to the efficiency of the code.
AK - 44 CHASSIS STV224X Video processor The STV2246/2247/2248 are fully bus controlled ICs for TV including PIF, SIF, luma, Chroma and deflection processing. Used with a vertical frame booster (TDA1771 or TDA8174 for 90° chassis, STV9306 for 110° chassis), they allow the design of multi-standard sets with very few external components and no manual adjustments.
AK - 44 CHASSIS 8. Not connected 9. Not connected 10. Symmetrical IF output 1 11. Symmetrical IF output 2 Band switching table: Low band Mid band High band Pin 3 0V 0V +5V Pin 4 0V +5 V 0V Pin 5 +5 V 0V 0V General description of UV1316 The UV1316 tuner belongs to the UV 1300 family of tuners, which are designed to meet a wide range of applications. It is a combined VHF, UHF tuner suitable for CCIR systems B/G, H, L, L’, I and I’.
AK - 44 CHASSIS TDA7266/TDA7266L General Description of TDA7266L The TDA7266L is a mono bridge amplifier specially designed for TV and Portable Radio applications. Requires very few external components WIDE SUPPLY VOLTAGE RANGE (3-18 V) MINIMUM EXTERNAL COMPONENTS. – NO SVR CAPACITOR – NO BOOTSTRAP – NO BOUCHEROT CELLS – INTERNALLY FIXED GAIN STAND-BY & MUTE FUNCTIONS SHORT CIRCUIT PROTECTION THERMAL OVERLOAD PROTECTION Pinnig 1 N.C. 2 N.C.
AK - 44 CHASSIS TDA8174AW INDEPENDENT VERTICAL AMPLITUDE ADJUSTMENT. BUFFER STAGE. POWER AMPLIFIER. FLYBACK GENERATOR. THERMAL PROTECTION. INTERNAL REFERENCE VOLTAGE DECOUPLING. General Description TDA8174A and TDA8174AW are a monolithic integrated circuits. It is a full performance and very efficient vertical deflection circuit intended for direct drive of a TV picture tube in Color and B & W television as well as in Monitor and Data displays. Pinning 1. POWER OUTPUT 2. OUTPUT STAGE Vs 3. TRIGGER INPUT 4.
AK - 44 CHASSIS MC44608 General description The MC44608 is a high performance voltage-mode controller designed for off–line converters. This high voltage circuit that integrates the start–up current source and the oscillator capacitor, requires few external components while offering a high flexibility and reliability. The device also features a very high efficiency stand–by management consisting of an effective Pulsed Mode operation.
AK - 44 CHASSIS Furthermore, pilot levels and identification signals can be evaluated internally with subsequent switching between mono/ stereo/bilingual; no I2C interaction is necessary (Automatic Sound Selection). The MSP 34x0G can handle very high FM deviations even in conjunction with NICAM processing. This is especially important for the introduction of NICAM in China. The ICs are produced in submicron CMOS technology.
AK - 44 CHASSIS TDA1308 Features Wide temperature range Excellent power supply ripple rejection Low power consumption Short-circuit resistant High performance high signal-to-noise ratio low distortion Pinning, Pin Value 1. Output A (Voltage swing): Min: 0.75 V, Max: 4.25 V 2. Inverting input A: Vo (clip): Min: 1400 mVrms 3. Non-inverting input A: 2.5 V 4. Ground: 0 V 5. Non-inverting input B: 2.5 V 6. Inverting input B: Vo (clip): Min: 1400 mVrms 7. Output B (Voltage swing): Min: 0.75 V, Max: 4.25 V 8.
2 IC 22 MC 44608 SMPS IR SENSOR KEYPAD NVM SERVICE CONNECTOR PLL/VST TUNER UV1315/1316 +8V +5V +5V St-by 115V +12V AUD. IF SCART1 FAV MONO R L STV2248C VIDEO PROCESSOR VIDEO SWITCHING CIRCUITS ST92195 MICRO CONTROLLER QSS HP. AMP. TDA1308 MSP 34X0G STEREO SOUND GENERAL BLOCK DIAGRAM of 11AK44 HORIZONTAL DRIVE BU808DF TDA8174AW VER AMP TDA6107 RGB AMP TDA7266/7266L AU. AMP FBT CRT AK - 44 CHASSIS 13.
AK - 44 CHASSIS 14. SERVICE MENU 14.1 Service Menu entrance All system, geometry and white balance alignments are performed in Service Mode. Before starting the service mode alignments, make sure that all manual adjustments are done correctly. To enter the service mode: 1. Press the MENU (30) button on the remote control gun. See figure 5. 2. Press digit keys 4, 7, 2 and 5 consecutively. When the Service Mode is entered the following On Screen Display appears (figure 4): Figure 4. Service Mode Figure 5.
AK - 44 CHASSIS Register APR BRI CON COL SHA HUE VOL WR-R WG-R WB-R FMP1 NIP1 SCP1 SEC1 FMP2 NIP2 SCP2 SEC2 F1H F1L F2H F2L BS1 BS2 BS3 CB OP1 OP2 OP3 OP4 OP5 TX1 GEOM OP8 Parameter Notes Default Values A51EFS13X191 A51ELD032X001 APR Threshold 10 4 Factory Setting Brightness 31 31 Factory Setting Contrast 49 49 Factory Setting Colour 26 26 Factory Setting Sharpness 6 6 Factory Setting Hue 31 31 Factory Setting Volume 9 9 White Point Adjust for Red (RGB mode) 48 30 White Point Adjust for Green (RGB 53 40
AK - 44 CHASSIS 14.3 Using Coloured Buttons By using the four coloured buttons on the remote control (24, 23, 13, 14) different features or adjust may be accessed. Figure 6. Coloured buttons Remote Control 14.3.1 AVL Press the RED button (23) to activate or deactivate the AVL (Automatic Volume Level, between different broadcast channels). 14.3.2 GEOMETRY MENU Press the GREEN button (24) in order to change from the Main Service Menu to the Geometry Menu, as shows the figure 7.
AK - 44 CHASSIS 14.3.2.1 Geometry Table Register VSIZ VPO S VSCO VCCO HSIZ HPO S HPIN HCCO HTRP VZSZ Param eter Vertical Size Default Values A51EFS13X191 A51ELD032X001 4:3 16:9 4:3 16:9 35 62 24 50 Vertical Position 11 16 12 16 Not used Not used Not used Horizontal Position Not used Not used Not used Not used 14 7 10 33 19 0 10 3 14 7 9 33 15 0 10 2 14 7 30 40 27 0 3 7 14 7 11 39 15 0 10 2 14.3.2.
AK - 44 CHASSIS 14.3.4 IF Adjustment Select IF1, IF2, IF3 or IF4. When the blue button (14) is pressed the before selected IF register is automatically adjusted. 14.4 Auto Programming System Set Up 1. Description In case the TV set should be serviced, there is the possibility of returning the set with the A.P.S. (Auto Programming System) activated in order to make easy the first start up to the customer. See the below figure.
AK - 44 CHASSIS 15.
AK - 44 CHASSIS OP4 – TV Features 7 1, Headphone is available (for STEREO models) 0, Headphone is not available 6 1, Arabic/Persian is Available in Menu Languages (for A, D, E, F, and later) 5 0, Arabic/Persian is NOT Available in Menu Languages 1, Hebrew is Available in Menu Languages (for A, D, E, F, and later) 0, Hebrew is NOT Available in Menu Languages 4 1, Hotel Mode can be activated 0, Hotel Mode can not be activated 3 1, No Signal Timer is enabled 0, No Signal Timer is disabled 2 For PLL Tuner
AK - 44 CHASSIS 16. LANGUAGES GROUP 1 GROUP 2 German Italian Dutch French Spanish Portuguese Swedish Norwegian Finnish Dannish English Greek Turkish English Polish Slovak Hungarian Russian Bulgarian Czech Rumanian Croatian 17. HOTEL MODE FUNCTIONS The following procedure details how to set up the Hotel Mode Functions. 1. Description The Hotel Mode deactivates Install and Program Features from the Main Features Menu. By other hand it can be reduced the Maximum Volume Level. 2.
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AK - 44 CHASSIS 19. HOW TO UPDATE THE TECHNICAL INFORMATION 19.1 How to update the Technical Information appeared on this Service Manual (and relatives) 19.1.1. Web site: https://www.vestelservice.com 19.1.2. Select: Technical Support 19.1.3. Login: 101278 19.1.4. Password: SHPII278 By this access you can consult the latest schematic diagram or request the Parts Listing of a concrete Production Date / Serial Number. By this way it can be also consulted the issued Technical Reports (Service Bulletins).
AK - 44 CHASSIS 19.4 Code Bar Label Information Product Code From the beginning of September.2002, the production month and year will be indicated inside the box as shown. Year Month Year Consecutive number Consecutive number Year Batch number Product code: It is the code that indicates Vestel internal identification number of the complete TV set. Year : Production year in two digits, e.g.: 02 for 2002 Month : Production month in two digits; e.g.: 04 for April.
AK - 44 CHASSIS Notes: 43
AK - 44 CHASSIS No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher. Technical information and Production: Vestel Electronik AS PRINTED BY: ON: Think Ecology, please use Technical information re-issued: SHARP ELECTRONICA ESPAÑA S.A. Service Manual Group Engineering Dept.
