Color TV Service Manual
Model: CT-21CBS5CPH Chassis:ETA-1 Model no.:CT-21CBS5CPH.doc version 1.
CONTENTS SAFETY INSTRUCTIONS AND MAINTENANCE .......................................................................... 4 SAFETY PRECAUTION .......................................................................................................................................... 5 PRODUCT SAFETY NOTICE ................................................................................................................................. 6 SAFETY SYMBOL DESCRIPTION ................................................
SERVICE SAFETY AND MAINTENANCE WARNING: BEFORE EXAMINING AND SERVICING THIS CHASSIS READ CAREFULLY THE FOLLOWING SAFETY INSTRUCTIONS. X-RAY RADIATION PRECAUTION 1. The EHT must be checked every time the TV is serviced to ensure that the CRT does not emit X-ray radiation as result of excessive EHT voltage. The maximum EHT voltage permissible in any operating circumstances must not exceed the rated value.
SAFETY PRECAUTION WARNING: REFER SERVICING TO QUALIFIED SERVICE PERSONNEL ONLY. 1. The TV has a nominal working EHT voltage. Extreme caution should be exercised when working on the TV with the back removed. a. Do not attempt to service this TV if you are not conversant with the precautions and procedures for working on high voltage equipment. b. When handling or working on the CRT, always discharge the anode to the TV chassis before removing the anode cap in case of electric shock. c.
PRODUCT SAFETY NOTICE CAUTION: FOR YOUR PROTECTION THE FOLLOWING PRODUCT SAFETY NOTICE SHOULD BE READ CAREFULLY BEFORE OPERATING AND SERVICING THIS TV SET. 1. Many electrical and mechanical components in this chassis have special safety-related characteristics. These characteristics are often passed unnoticed by a visual inspection and the X-ray radiation protection afforded by them cannot necessarily be obtained by using replacements rated at higher voltages or wattage, etc.
SAFETY SYMBOL DESCRIPTION Model no.:CT-21CBS5CPH.doc version 1.
MAINTENANCE 1. Place the TV set on a stable stand or base that is of adequate size and strength to prevent it from being accidentally tipped over, pushed off, or pulled off. Do not place the set near or over a radiator or heat register, or where it is exposed to direct sunlight. 2. Do not install the TV set in a place exposed to rain, water, excessive dust, mechanical vibrations or impacts. 3. Allow enough space (at least 10cm) between the TV and wall or enclosures for proper ventilation. 4.
MECHANICA DISASSEMBLIES CABINET BACK REMOVAL 1. Refer to Figure 1, remove 7screws. 2. Pull off cabinet back and remove. CHASSIS REMOVAL 1. Remove cabinet back. 2. Discharge the picture tube anode (2nd anode lead) to the dag coating (picture tube grounding lead). 3. Disconnect Degaussing coil socket (KE). Picture tube socket, Deflection yoke connector (KDY). Speaker connectors (KL and KR), and 2nd anode lead. 4. Remove chassis completely by sliding it straight back. Model no.:CT-21CBS5CPH.
PICTURE TUBE REMOVAL CAUTION: Do not disturb the deflection yoke or magnet assembly on the picture tube Neck. Care must be taken to keep these assemblies intact, unless picture tube is being replaced. Discharge the picture tube to the coating before handing the Tube. 1. Remove chassis, referring to Chassis Removal instructions. 2. Place cabinet front face down on the soft surface. 3. Remove the screw one ach corner of the picture tube and GENTLY lift the picture tube out of the cabinet. 4.
ADJUSTMENTS SET-UP ADJUSTMENTS The following adjustments should be made when a complete realignment is required or a new picture tube is installed. Perform the adjustments in the following order: 1. Color purity 2. Convergence 3. White balance Notes: 1. The purity/convergence magnet assembly and rubber wedges need mechanical ositioning. Refer to Fig1, 2. 2. For some picture tubes, purity/ convergence adjustments are not required. 1.
2. Convergence Adjustment Preparation: Before attempting any convergence adjustment, the TV should be operated for at least 15 minutes. 2.1 Center convergence adjustment 2.1.1 Receive dot pattern. 2.1.2 Adjust the brightness/contrast controls to obtain a sharp picture. 2.1.3 Adjust two tabs of the 4-pole magnet to change the angle between them and red and blue vertical lines are superimposed each other on the center of the screen. Fig. 1 2.1.
3. White Balance Adjustment Generally, white balance adjustment is made with professional equipment. It’s not practical to get good white balance only through manual adjustment. For TVs with I²C bus control, change the bus data to adjust white balance. Fig. 2 Fig.3 Model no.:CT-21CBS5CPH.doc version 1.
CIRCUIT ADJUSTMENTS Preparation: Circuit adjustments should be made only after completion of set-up adjustments. Circuit adjustments can be performed using the adjustable components inside the TV set. For TVs with I2C bus control, first change the bus data. 1. Degaussing A degaussing coil is built inside the TV set. Each time the TV is powered on, the degaussing coil will automatically degauss the TV.
3. High Voltage Inspection Measure voltages of test points on the main PCB with the digital voltmeter. Measure the CRT high voltage with the high-voltage testing equipment and heater voltage with the high-frequency effective voltmeter. The rated values are shown as below. Table 2 Test Point Negative of VD461 Negative of VD485 CRT Anode Heater Voltage (V) 26 / 1V 190 / 5V 27 / 1.5KV 6.3 / 0.3Vrms 4. Focus Adjustment Caution: Dangerously high voltages are present inside the TV.
6. SERVICE mode 6.1 To enter the DESIGN/SERVICE mode Set the volume to 0. Then press and hold the MUTE button on the remote control, and press the MENU button on the TV to enter the SERVICE mode. In this case, red “s” is displayed on the upper center of the screen. To exit from the S mode, turn off the TV set by the POWER button on the remote control. Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing.
Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
STRUCTURE and CHASSIS FUNCTION DESCRIPTION 1. BLOCK DIAGRAM Model no.:CT-21CBS5CPH.doc version 1.
2. CHASSIS DESCRIPTION General Description ETA-1 chassis is applied in SF21GA63 series. By use of Toshiba V/C/D-MCU 2IN1 IC for TV small signal processing and bus control, the chassis enables TV tuning, adjustment, control and picture correction, featuring high-integration, high-performance-to-price ratio and high-reliability and compact circuit with fewer external components. The chassis, widely used in small and medium TVs, provides much more convenience for manufacturing and technical service.
SERVICE DATA TECHNICAL DATA OF KEY ICS 1.MCU and Signal Processor for a PAL/NTSC TV TMPA8873CMANG /CPANG/CRANG /CSANG 1.General Description The TMPA8873CPANG is an integrated circuit for a PAL/NTSC TV. A MCU and a TV signal processor are integrated in a 64-pin shrink DIP package. The MCU contains 8-bit CPU, ROM, RAM, I/O ports, timer/counters, A/D converters, an on-screen display controller, remote control interfaces, IIC bus interfaces and the Closed Caption decoder.
2. FEATURE Model no.:CT-21CBS5CPH.doc version 1.
3. BLOCK DIAGRAM Model no.:CT-21CBS5CPH.doc version 1.
4.Basic Structure 1. Internal Connections TMPA8873 has two pieces of IC chip in one package, using Multi-Chip-Package (MCP) technology. One is a micro controller (MCU) and the other one is a signal processor (SP) for a color TV. There are some internal connections between these two ICs for handling below signals. No.
5. TERMINAL INTERFACE Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
SIGNAL PROCESSOR BLOCK Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
Model no.:CT-21CBS5CPH.doc version 1.
Microcontrollers Descriptions (MROM version: TMPA8873CMANG / CPANG / CRANG /CSANG) Model no.:CT-21CBS5CPH.doc version 1.
2. TFA9842AJ 2-channel audio amplifier with volume control (SE: 1 W to 7.5 W) 1. General Description The TFA9842AJ contains two identical audio power amplifiers. The TFA9842AJ can be used as two Single-Ended (SE) channels with a volume control. The maximum gain is 26 dB. The TFA9842AJ comes in a 9-pin DIL-bent-SIL (DBS9P) power package. The TFA9842AJ is pin compatible with the TFA9843AJ, TFA9843(B)J, TFA9842(B)J and TFA9841J.
3. Block Diagram Model no.:CT-21CBS5CPH.doc version 1.
4.2 Pin Description Model no.:CT-21CBS5CPH.doc version 1.
4. VERTICAL SCAN OUTPUT STAGE CIRCUIT LA78040/LA78041 Both LA78040/LA78041 are vertical scan output stage power amplifiers. But there is a little bit difference between the two amplifiers, that is, LA78040 has supply voltage of 24V and output current of 1.8AP-P while LA78041 has supply voltage of 30V and output current of 2.2AP-P.
5. EEPROM AT24C04/08/16 1) Features Low-voltage and Standard-voltage Operation -2.7 (Vcc=2.7V to 5.5V) -1.8 (Vcc=1.8V to 5.5V) Internally Organized 128x8(1K), 256x8 (2K), 512x8 (4K), 1024x8 (8K) or 2048x8 (16K) 2-wire Serial Interface Schmitt Trigger, Filtered Inputs for Noise Suppression Bi-directional Data Transfer Protocol 100kHz (1.8V, 2.5V, 2.
3) Pin Configuration 4) Pin Description SERIAL CLOCK (SCL): The SCL input is used to positive edge clock data into each EEPROM device and negative edge clock data out of each device. SERIAL DATA (SDA): The SDA pin is bi-directional for serial data transfer. This pin is open-drain driven and may be wire-ORed with any number of other open-drain or open-collector devices.
Table 13 WP PIN Status At Vcc At GND Part of the Array Protected 24C02 24C04 24C08 Normal Full (1K) Full (2K) Full (4K) Read / Write Array Array Array Operation Normal Read / Write Operation 24C01A 5) Memory Organization AT24C01A, 1K SERIAL EEPROM: Internally organized with 16 pages of 8 bytes each, the 1K requires a 7-bit data word address for random word addressing.
7. SWITCH-MODE POWER SUPPLY IC STRG5653/G8656 1). General Description The STRG5653/G8656 are part of the STRG5600/G8600 series thick-film ICs for switch-mode power supply incorporating power MOSFET with a high-precise error amplifier. The ICs feature fewer external components, small-size and standard power supply. The series STR-G8600 use Chip on Chip technology with the same operation principle as STR-G5600. Pin configuration, function and threshold of STR-G8600 are compatible with those of STR-G5600.
SERVICE DATA OF KEY ICs Table 16 Ground Resistance of TMPA8873 Pins Model no.:CT-21CBS5CPH.doc version 1.
Table 17 Operating Voltage of TMPA8873(N202)’s Pins Model no.:CT-21CBS5CPH.doc version 1.
Table 18 Functions and Service Data TFA9842J’s Pins Table 20 Functions and Service Data LA78040’s Pins Model no.:CT-21CBS5CPH.doc version 1.
Table 21 Functions and Service Data of AT24C08 / 16 Pins Table 22 Functions and Service Data of STR-G5653’S Pins Model no.:CT-21CBS5CPH.doc version 1.
APPENDIX Model no.:CT-21CBS5CPH.doc version 1.
REPLACEMENT PARTS LIST PART CODE 883370281G007 54111A04180 54111A04180 54111A04180 56281310080 8475900210B 681C21F1CH3 8864001520C 50990011200 8782000060G 51113681JU0 51113102JU0 51113152JU0 51113222JU0 51113472JU0 51113103JU0 50620071780 50620071650 50620071200 50620071350 513154P7J40 50620101590 50620102710 50620050240 51516P47J10 50620080290 51C20090M00 50640021950 52532102K10 50640021630 50640063120 50640022370 5254F102M10 5254F102M10 5254F102M10 52582102M30 52592471K30 50640022840 52592681K30 5246Q
PART CODE 51113331JU0 51113103JU0 50620101330 50620102500 50620103000 50620102940 51516P27J70 51517010J90 52532392K10 52542221K20 52542102K10 5236C104J10 52617470M11 52616471M11 50640062010 50640062630 50640062140 84739003100 611120RU251 611120U1C45 50660091870 61212082CT5 62123830YT7 62423830O05 51113222JU0 51113392JU0 50620101520 51113473JU0 50620071420 511241P5JT0 51224123J20 50620030150 5251C180J10 50640023020 52367104J10 52369104J10 50640062160 52616471M11 52616101M11 52617010MV0 611120RU251 612160
PART CODE 5253F103Z10 PART NAME CERAMIC CAP. SPECIFICATION CT1-63V-08C-2F4-10NFZ 52532102K10 52532222K10 50640011520 52367104J10 52367224J10 50640062240 CERAMIC CAP. CERAMIC CAP. MYLAR CAP. MYLAR CAP. MYLAR CAP. ELECTROLYTIC CAP. CT1-63V-06C-2B4-1000PFK CT1-63V-08C-2B4-2200PFK CL21X-50V-8200PFJ CL21X-50V-0.1μFJ CL21X-50V-0.22μFJ CD110X-50V-10μFM 1 1 1 3 1 9 52617P47M11 52617010MV0 50640062820 50640062270 52617470M11 50630061080 50630061390 61411075DT0 ELECTROLYTIC CAP. ELECTROLYTIC CAP.
PART CODE 50620071930 50620072160 51113471JU0 51113681JU0 50620072000 51113102JU0 51113392JU0 50620071130 50620103320 52532471K10 52532331K10 50640021650 5254F102M10 50640024840 52592102J20 52613471M11 52617P47M11 50640062240 50640061890 61411075DT0 61411075DT0 62210150YW0 62118150Y16 62126880010 50650030510 50910010000 5360861F000 8782011250C 51113512JU0 51C08013006 51113103JU0 51113183JU0 50620073010 54167605410 8782012980C 51113101JU0 51113333JU0 50640062240 67109138025 67109138025 67109138045 878201