Changhong Electric PF29T18 Service Manual
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Changhong Electric PF29T18 Service Manual

Changhong Electric PF29T18 Service Manual

Chassis no. ch-20
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FILE NO. SM-CTV-O-123
COLOR TELEVISION
SERVICE MANUAL
MODEL NO. PF29T18/34T18
/ CPF29T99
CHASSIS NO. CH-20
Please read this manual carefully before service.

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  • Page 1 FILE NO. SM-CTV-O-123 COLOR TELEVISION SERVICE MANUAL MODEL NO. PF29T18/34T18 / CPF29T99 CHASSIS NO. CH-20 Please read this manual carefully before service.
  • Page 2 TABLE OF CONTENTS SAFETY INSTRUCTIONS..................1 ADJUSTMENTS ..................... 4 STRUCTURE AND CHASSIS FUNCTION DESCRIPTION ........17 SERVICE DATA ....................17 REPLACEMENT OF PARTS.................. 55 APPENDIX 1. CIRCUIT DIAGRAMS 2. PRINTED CIRCUIT BOARD LAYOUTS 3. FINAL ASSEMBLY DIAGRAMS 4. FINAL WIRING DIAGRAMS...
  • Page 3 SERVICE MANUAL INSTRUCTIONS FOR SERVICE SAFETY AND MAINTENANCE “ WARNING: BEFORE SERVICING THIS CHASSIS, READ THE X-RAY ” “ ” “ RADIATION PRECAUTION SAFETY PRECAUTION PRODUCT ” SAFETY NOTICE INSTRUCTION BELOW. 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.
  • Page 4 SERVICE MANUAL 6. When remounting the TV chassis, ensure that all guard devices, such as nonmetal control buttons, switch, insulating sleeve, shielding cover, isolating resistors and capacitors, are installed on the original place. 7. Replace blown fuses within the TV with the fuse specified in the parts list. 8.
  • Page 5 SERVICE MANUAL have special safety-related characteristics. C UL This symbol tells you that the critical components identified by the C-UL marking have been evaluated to the UL and C-UL standards and have special safety-related characteristics. This symbol tells you that the critical components identified by the VDE marking have special safety-related characteristics.
  • Page 6 SERVICE MANUAL 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...
  • Page 7 SERVICE MANUAL 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 2.1.4 Turn both tabs at the same time keeping the angle constant to superimpose red and blue horizontal on the center of the screen.
  • Page 8 SERVICE MANUAL the bus data to adjust white balance. Fig. 2 4-pole Magnet Movement 6-pole Magnet Movement Center Convergence by Convergence Magnets Incline the Yoke Up (or Down) Incline the Yoke Right (or Left) Circumference Convergence by DEF Yoke Fig.3...
  • Page 9 SERVICE MANUAL 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 I C bus control, first change the bus data. 1.
  • Page 10 SERVICE MANUAL Positive of C434 13.5V±1V Positive of C840 8V±0.5V One Pin of 326 12V±1V Positive of C424 5V±0.5V Heater 6.3V±0.3Vrms 29KV±1.5KV (For 29” CRT) CRT anode voltages 31.0KV±1.5KV (For 34” CRT) 3. High Voltage Inspection Caution: No high voltage adjustment components inside the chassis. Please perform high voltage inspection in the following ways.
  • Page 11 SERVICE MANUAL 5. SERVICE mode 5.1 To enter the SERVICE mode Set the volume to 0 by the remote control. Then press and hold the MUTE button on the remote control and MENU button on the TV at the same time for over 2 seconds. In the S mode, press the POWER button to quit the S mode.
  • Page 12 SERVICE MANUAL RAGC Set to the optimal mode AGC adjustment（19—1E recommended） AV output volume control for TDA7442 PWL clip level（5%） White peak limit IF phase lock PEAK Blue extension Black stretch CON100 Sub contrast CON50 BRI100 Sub brightness BRI50 COL100 Sub color SHP100 Sub sharpness...
  • Page 13 ( not for TDA7442) MEFF MAMP MHAR MDB setting (not for TDA7442) MLOP MHIP F8 (For PF29T18/34t18 only) Option set byte 1 D8 (For CPF29T99 only) Option set byte 2 Option set byte 3 Option set byte 4 Option set byte 5...
  • Page 14 SERVICE MANUAL OP_TILT Tilt correction OP_FSL 1: Black screen available when changing channels; OP_BSCREEN 0: Black screen not available when changing channels OP_5060 OP_DK 1: D/K option OP_BG 1: B/G option OP_I 1: I option OP_L 1: L option OP_AUTO_SOUND 1: MSP3410；0: TDA7442 OP_EQUAL 1: MSP3410；0: TDA7442...
  • Page 15 SERVICE MANUAL OP_HOLAND OP_SUOMI OP_GREECE OP_ITALY OP_NORWAY OP_PORTUAL OP_SWEDEN OP_TURKY Note : ① Bit6, Bit5, Bit4 in OP5 are outgoing audio option settings as follows: 000: East Europe (D/K); 001: West Europe (B/G); 010: UK (I); 110: France (L); 100: Europe (Auto). ②...
  • Page 16 SERVICE MANUAL STRUCTURE AND CHASSIS FUNCTION DESCRIPTION 1. Structure Block Diagram R/L2 Out CTRL SIG R/L2 In CVBS 2 CTRL SIG AV-CVBS R/L3 In AV-CVBS CVBS 1 In R/L1 In TV-CVBS R/L1 Out R/G/B Input Audio Out...
  • Page 17 SERVICE MANUAL 2. Block Diagram for Supply Voltage System Switch Transformer BCK-24339L VD815 VD819 Filament HV FV SV Voltage FBT T402...
  • Page 18 SERVICE MANUAL 3. Chassis Description General Description CH-20 chassis is applied in CPF29T99/PF29T18/34T18, which mainly uses Philips’ advanced UOC-ultimate one chip TDA959X and I C-bus controlled IC. With combination of microcontroller small signal processor, TDA959X features high-integrity, high-performance-to-price ratio and high-reliability and advanced functions with fewer external components, which provide much more convenience for manufacturing and technical service.
  • Page 19 SERVICE MANUAL SERVICE DATA 1. Technical Data of Key ICs 1.1 Microcontroller and Small Signal Processor TDA959X (1) General Description The various versions of the TDA959X H/PS-N1 series combine the functions of a video processor together with a m-Controller and US Closed Caption decoder. Most versions have a Teletext decoder on board.
  • Page 20 SERVICE MANUAL ● Vertical count-down circuit ● Vertical driver optimized for DC-coupled vertical output stages ● Horizontal and vertical geometry processing ● Horizontal and vertical zoom function for 16 : 9 applications ● Horizontal parallelogram and bow correction for large screen picture tubes ●...
  • Page 21 SERVICE MANUAL Data Capture ● Text memory for 1 or 10 pages ● In the 10 page versions inventory of transmitted Teletext pages stored in the Transmitted Page Table (TPT) and Subtitle Page Table (SPT) ● Data Capture for US Closed Caption ●...
  • Page 22 SERVICE MANUAL (3) Functional Difference between the Various IC Versions Table 5 9590PS 9591PS 9592PS 9593PS 9594PS 9590H IC Version (TDA) 9591H 9592H 9593H 9594H TV range 110 110 Mono intercarrier multi-standard sound demodulator (4.5 - 6.5 MHz) √ √ √...
  • Page 23 SERVICE MANUAL (4) Pinning (QFP-80 ENVELOPE) Symbol Description QFP-80 SDIP-64 P3.1/ADC1 port 3.1 or ADC1 input P3.2/ADC2 port 3.2 or ADC2 input P3.3/ADC3 port 3.3 or ADC3 input VSSC/P digital ground for m-Controller core and periphery P0.5 port 0.5 (8 mA current sinking capability for direct drive of LEDs) port 0.6 (8 mA current sinking capability for direct drive of LEDs) or P0.6/CVBSTD Composite video input.
  • Page 24 SERVICE MANUAL Symbol Description QFP-80 SDIP-64 CVBS2 external CVBS2 input ground for TV-processor CVBS3/Y CVBS3/Y input chroma input WHSTR white stretch capacitor CVBSO CVBS output AUDOUT /AMOUT audio output /AM audio output (volume controlled) scan velocity modulation output INSSW2 2nd RGB / YUV insertion input R2/VIN 2nd R input / V (R-Y) input / PR input G2/YIN...
  • Page 25 SERVICE MANUAL (5) Black Diagram...
  • Page 26 SERVICE MANUAL (6) Pining XTALOUT P3.1/ADC1 XTALIN P3.2/ADC2 OSCGND P3.3/ADC3 VDDC VSSC/P P0.5 VDDA P0.6/CVBSTD VSSA SECPLL TDA959X series DECDIG BLKIN PH2LF BCLIN QFP-80 PH1LF B2/UIN GND3 G2/YIN DECBG R2/VIN INSSW2 VDRB VDRA AUDOUT/AMOUT IFIN1 CVBSO IFIN2 WHSTR IREF CVBS3/Y AGCOUT DVBIN1/SIFIN1 CVBS2...
  • Page 27 SERVICE MANUAL P1.3/T1 P1.2/INT0 P1.6/SCL P1.1/T0 P1.0/INT1 P1.7/SDA P2.0/TPMW VDDP P3.0/ADC0 RESET P3.1/ADC1 XTALOUT P3.2/ADC2 XTALIN P3.3/ADC3 OSCGND VSSC/P VDDC P0.5 P0.6 VDDA VSSA SECPLL DECDIG BLKIN BCLIN PH2LF B2/UIN PH1LF G2/YIN GND3 R2/VIN DECBG INSSW2 VDRB VDRA CVBS/Y IFIN1 IFIN2 IREF CVBS1...
  • Page 28 SERVICE MANUAL 1.2 EEPROM AT24C16 (N101) (1) Features ・ Low Voltage and Standard Voltage Operation ・ 8-Pin and 14-Pin JEDEC SOIC and 8-Pin 5.0 (V = 4.5V to 5.5V) PDIP Packages 2.7 (V = 2.7V to 5.5V) 2.5 (V = 2.5V to 5.5V) (2) Description 1.8 (V = 1.8V to 5.5V)
  • Page 29 SERVICE MANUAL (4) Block Diagram Fig. 11 (5) Refer to Table 13 about Functions and Data of the IC’s Pins.
  • Page 30 SERVICE MANUAL 1.3 Tone Control and Surround Digitally Controlled Audio Processor TDA7442/TDA7442D (1) Features 4 Stereo Inputs Input Attenuation Control In 0.5db Step Treble And Bass Control Two Surround Mode Available With 4 Selectabler Responses: - Music - Simulated Stereo Two Speaker Attenuators: - 2 Independent Speaker Controls In 1db Steps For Balance Facility...
  • Page 31 SERVICE MANUAL (4) Block Diagram (TDA7442) 5.6K 5.6nF 100nF 100nF 100nF 2.2mF MONITOR(L) MUXOUT(L) TREBLE-L BIN(L) BOUT(L) 0.47mF 31.5dB control L-IN1 RPS1 0.47mF L-IN2 90Hz 0.47mF 79dB CONTROL L-IN3 SPKR 0.47mF SURR MUSIC/ LOUT SYMULATED SYMULATED L-IN4 MUTE MIXING MUSIC TREBLE BASS I 2 C BUS DECODER +LATCHES...
  • Page 32 SERVICE MANUAL 1.4 Sound Power Amplifier TDA8944J (N603) (1) General Description The TDA8944J is a dual-channel audio power amplifier with an output power of 2 × 7 W at an 8Ω load and a 12V supply. The circuit contains two Bridge Tied Load (BTL) amplifiers with an all-NPN output stage and standby/mute logic.
  • Page 33 SERVICE MANUAL 1.5 Triple Video Output Amplifier TDA6108JF/6107Q (1) Features (2) General Description Typical bandwidth 9.0MHz (for The TDA6107Q/6108JF includes three video TDA6108JF) or 5.5MHz (for TDA6107Q) output amplifiers in one plastic DIL-bent-SIL for an output signal of 60 V (peak-to-peak 9-pin medium power (DBS9MPF) package (SOT value) 111-1), using high-voltage DMOS technology,...
  • Page 34 SERVICE MANUAL Table 7 Pinning Symbol Description Inverting input 1 i(1) Inverting input 2 i(2) Inverting input 3 i(3) ground (fin) Black-current measurement output Supply voltage Cathode output 3 oc(3) Cathode output 2 oc(2) Fig. 13 Pin Configuration. Cathode output 1 oc(1) (5) Refer to Table 15 about Functions and Data of the IC’s Pins.
  • Page 35 SERVICE MANUAL 1.6 COMB Filter TC90A49P (N1) (1) Features ・ TV format : NTSC (3.58), PAL, M-PAL, and N-PAL ・ Dynamic comb filter ・ Vertical edge enhancement circuit ・ PLL 8 × multiplier circuit ・ Internal 8-bit 4 fsc AD converter ・...
  • Page 36 SERVICE MANUAL 1.7 Dual 4-channel Analog Multiplexer/Demultiplexer HEF4052 (1) Description The HEF4052 is a dual 4-channel analog multiplexer/demultiplexer with common channel select logic. Each multiplexer/demultiplexer has four independent inputs/outputs (Y to Y ) and a common input/output (Z). The common channel select logic includes two address inputs (A and A ) and an active LOW enable input (E).
  • Page 37 SERVICE MANUAL Fig. 19 Schematic Diagram (One Switch) (3) Function Table Table 9 Inputs Channel none Notes H=HIGH state (the more positive voltage) L=LOW state (the less positive voltage) X=state is immaterial Ratings Limiting values in accordance with the Absolute Maximum System (IEC 134) Supply voltage (with reference to V -18 to +0,5 V Note...
  • Page 38 SERVICE MANUAL 1.8 Vertical deflection output TDA8359J (1) Introduction The TDA8359J is an integrated power circuit for use in 90° and 110° colour deflection systems. It contains a vertical deflection bridge output, operating as a high efficiency class G system and can handle field frequencies from 25 to 200 Hz.
  • Page 39 SERVICE MANUAL (3) Block Diagram GUARD GUARD CIRCUIT i(p-p) OUTA V i(bias) INPUT FEEDB FEED BACK i(p-p) CIRCUIT i(bias) OUTB TDA8359J Fig. 21...
  • Page 40 SERVICE MANUAL 1.9 Switch-mode Power Supply STR- W68XX (1) General Description The STR-W6800 Series are thick-film ICs for Quasi-Resonant flyback SMPS with MOSFET and control built-in, featuring fewer external components, simplified circuit design, small-size and standard power supply. “STR-W6800 Series ICs” offers three operation modes: Quasi-Resonant, Multi-Bottom Skip and Time Fix Control, thus guaranteeing high efficiency in all loading areas by means of the automatic change-over of the operation modes.
  • Page 41 SERVICE MANUAL (3) Black Diagram 4 Pin Drive REG 1 Pin LATCH S/GND 3 Pin Current OCP/BD Mirror 5 Pin RTFC Current 7 Pin Mirror FB/OLP 6 Pin Fig. 22 (4) Pinning Table 11 Pin No. Symbol Name Function Description Source for MOSFET S/GND Source/ GND for Control...
  • Page 42 SERVICE MANUAL 2. WAVEFORMS OF KEY POINTS Waveform during C802 Startup Waveform during +B Voltage Startup...
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  • Page 47 SERVICE MANUAL Waveform during V404’s Base T=64us...
  • Page 48 SERVICE MANUAL Waveform during V404’s C Electrode...
  • Page 49 SERVICE MANUAL...
  • Page 50 SERVICE MANUAL 3. SERVICE DATA OF KEY ICS Table 12 Functions and Service Data of TDA9594H (N101)’s Pins Resistance to Ground Reference Voltage Pin No. Function Description (KΩ) P3.1/ADC1 P3.2/ADC2 P3.3/ADC3 0.196 VSSC/P P0.5 10.4 P0.6/CVBSTD 10.4 VSSA SECPLL 5,420 7.68 DECDIG 30.6...
  • Page 51 SERVICE MANUAL AVL/REF0/SNDIF/REFIN (1) 3,680 AUDIO2 AUDIO3 HOUT 7,660 FBISO 1,360 DECSDEM 5,290 QSSO/AMOUT/ 3,690 AUDEEM (1) EHTO 2.54 PLLIF 5,440 SIFAGC/DVBAGC (1) 5,000 INTCO/DVBO (1) IFVO/SVO/DVBO (1) 3,660 2.05 CVBS1 5,230 CVBS2 5,380 CVBS3/Y 5,340 3.74 82.3 1.47 WHSTR 5,190 CVBSO 5,500...
  • Page 52 SERVICE MANUAL VDDA 0.28 VDDC 0.28 OSCGND 0.014 XTALIN 2,500 XTALOUT RESET VDDP 0.28 P1.0/INT1 0.06 P1.1/T0 0.06 P1.2/INT0 12,200 P1.3/T1 0.19 P1.6/SCL P1.7/SDA P2.0/TPWM 10.5 0.06 P2.1/PWM0 P2.2/PWM1 0.06 P2.3/PWM2 0.05 P2.4/PWM3 P2.5/PWM4 10.6 SYNC_FILTER 3,700 P3.0/ADC0...
  • Page 53 SERVICE MANUAL Table 13 Functions and Service Data of AT24C16 (N102)’s Pins Digital Multimeter Functions Description Reference Voltage Positive Resistance Negative Resistance (20KΩ) (20KΩ) Address input Address input Address input Common ground Serial data 6.37 Serial clock input 6.37 6.44 Write protect Supply voltage 3.03...
  • Page 54 SERVICE MANUAL Not connected ∞ ∞ Negative loudspeaker terminal 2 ∞ ∞ Ground channel 2 Supply voltage channel 2 14.8 Positive loudspeaker terminal 2 ∞ ∞ Table 15 Functions and Service Data of TDA6107Q/TDA6108JF (NY01)’s Pins Digital Multimeter Function Description Pin No.
  • Page 55 SERVICE MANUAL ADC input range D upper limit voltage. Stabilize by attaching a 3.15 0.64 0.63 0.01µF capacitor. ADC input. Inputs 1.0 Vp-p video 2.14 ∞ ∞ signal. Sync tip clamp is performed. ADC input range D lower limit voltage. Stabilize by attaching a 1.84 0.497 0.49...
  • Page 56 SERVICE MANUAL Table 17 Functions and Service Data of HEF4052 (N301/N302)’s Pins Digital Multimeter Function Description Reference Voltage (V) Positive Resistance (KΩ) Negative Resistance (KΩ) Signal input 12.52 6.46 Signal input 12.5 6.46 Signal input 12.52 6.46 Signal output 12.43 6.25 Signal input 12.5...
  • Page 57 SERVICE MANUAL REPLACEMENT OF PARTS 1. Description Many electrical and mechanical components in this chassis have special safety-related characteristics. Components which have these special safety characteristics in this manual and its supplements are identified by the international hazard symbols or UL, FCC, FDA or VDE marking on the circuit diagram and parts list.
  • Page 58 APPENDIX: Circuit Diagram (1) This circuit diagram is only for reference, specifications are subject to change without reference. Which have the same characteristics as original parts. Cold ground Hot ground 1. Any components identified by have special safety-related characteristics. Use replacement...
  • Page 59 Circuit Diagram (2)
  • Page 60 MAIN PCB...
  • Page 61 CRT RGB PCB...

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