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Daewoo DTE-29G3ZZR Service Manual Download Page 65

 Appendix                                                                                                     Service manual CP-795

 

- 40 - 

On normal run mode, I501 microcontroller pin 63 (power) is set to high 
 

• 

So, I810 controlled rectifier is not conducting 

 

- Q809 is conducting. So, Q808 is not conducting and Q807 is conducting 
- So, Q807 collector is connected to the ground and I810 controlled rectifier gate pin is set 

to low (no conducting) 

 

• 

So, current from 11V DC voltage (from T801 SMPS transformer pin 13) does not flow through Q811 
and Q810 transistors but flows through I806 IC error amplifier 

 

- Q809 is conducting. So, Q810 is not conducting and no current flows from Q810 collector 

to the ground 

 
Therefore, the power circuit diagram is the following one: 
 
2-9-2-1-2 power supply circuit diagram during TV set normal run 
 

 

Summary of Contents for DTE-29G3ZZR

Page 1: ...eaker 12W 8 ohm X 2 Teletext System 10page memory FASTEXT FLOF or top Aerial input 75ohm unbalanced Channel coverage Off air channels S cable channels and hyperband Tuning System Frequency synthesiser tuning system Visual screen size 68cm DIAGONAL Channel indication On Screen Display Program Selection 100programmes Aux terminal EURO SCART1 Audio Video In and Out R G B In slow and fast switching EU...

Page 2: ...1 BLOCK DIAGRAM 21 IF 25 SOURCE SWITCHING 27 U CONTROLLER I O PIN CONFIGURATION AND FUNCTION 27 SOUND PROCESSING 28 SOUND AMPLIFICATION 31 VERTICAL DEFLECTION 31 POWER SUPPLY 33 TV START UP TV NORMAL RUN AND STAND BY MODE OPERATIONS 37 MAIN FEATURES 2 SPECIFICATIONS 2 CHANNEL TABLE 4 SAFETY INSTRUCTION 9 CIRCUIT BLOCK DIAGRAM 10 ALIGNMENT INSTRUCTIONS 11 MICROCONTROLLER CONFIGURATION SERVICE MODE ...

Page 3: ...Audio Video Jack on front of cabinet in common connection with EURO SCART 2 Headphone jack 3 5 mm on front of cabinet Remote Control Unit R 40A13 1 Main features 1 1 Specifications 21 Pin EURO SCART 1 Pin Signal Description Matching value 1 Audio Output Right 0 5 Vrms Impedance 1 RF 54 Mod 2 Audio Input Right 0 5Vrms Impedance 10 3 Audio Output Left 0 5 Vrms Impedance 1 RF 54 Mod 4 Audio Earth 5 B...

Page 4: ...o Input Right 0 5Vrms Impedance 10 3 Audio Output Left 0 5 Vrms Impedance 1 RF 54 Mod 4 Audio Earth 5 Earth 6 Audio Input Left 0 5Vrms Impedance 10 7 N C 8 N C 9 N C 10 N C 11 N C 12 N C 13 Earth 14 Earth 15 Chroma Input 3dB for a luminance signal of 1Vpp 16 N C 17 Video Out Earth 18 Video In Earth 19 Video Output 1Vpp 3dB Impedance 75 20 Video Input Y In 1Vpp 3dB Impedance 75 21 Common Earth ...

Page 5: ...20 C21 471 25 471 25 471 25 471 25 C22 479 25 479 25 479 25 479 25 C23 487 25 487 25 487 25 487 25 C24 495 25 495 25 495 25 495 25 C25 503 25 503 25 503 25 503 25 C26 511 25 511 25 511 25 511 25 C27 519 25 519 25 519 25 519 25 C28 527 25 527 25 527 25 527 25 C29 535 25 535 25 535 25 535 25 C30 543 25 543 25 543 25 543 25 C31 551 25 551 25 551 25 551 25 C32 559 25 559 25 559 25 559 25 C33 567 25 56...

Page 6: ... 25 815 25 815 25 815 25 C65 823 25 823 25 823 25 823 25 C66 831 25 831 25 831 25 831 25 C67 839 25 839 25 839 25 839 25 C68 847 25 847 25 847 25 847 25 C69 855 25 855 25 855 25 855 25 C70 863 25 863 25 863 25 863 25 C71 69 25 C72 76 25 C73 83 25 C74 90 25 C75 97 25 C76 59 25 C77 93 25 S01 105 25 104 75 103 25 105 25 S02 112 25 116 75 111 25 112 25 S03 119 25 128 75 119 25 119 25 S04 126 25 140 75...

Page 7: ...343 25 S27 351 25 351 25 351 25 351 25 S28 359 25 359 25 359 25 359 25 S29 367 25 367 25 367 25 367 25 S30 375 25 375 25 375 25 375 25 S31 383 25 383 25 383 25 383 25 S32 391 25 391 25 391 25 391 25 S33 399 25 399 25 399 25 399 25 S34 407 25 407 25 407 25 407 25 S35 415 25 415 25 415 25 415 25 S36 423 25 423 25 423 25 423 25 S37 431 25 431 25 431 25 431 25 S38 439 25 439 25 439 25 439 25 S39 447 2...

Page 8: ... I Group III It contains all the programs with a weak signal strength which are not listed in group I Group IV If two or more programs with the same code are found only the strongest or if they have the same level the one with the lowest frequency is listed in group I II or III The others are listed in group IV Note If two programs with the same name but a different code are found these two progra...

Page 9: ...B Note for satellite receiver users Before startingATSS turn On your satellite receiver and tune SKY NEWS If GB is selected the TV controlling software seeks for programs only in UHF C21 to C70 The sorting order is 1 BBC1 2 BBC2 3 ITV 4 CH4 5 CH5 6 NEWS If two or more identical programs same name but different code e g BBC1 and BBC1 Scotland are found the following programs in the list will be shi...

Page 10: ... 2 Discharge the high potential of the picture tube before handling the tube The picture tube is highly evacuated and if broken glass fragments will be violently expelled 2 If any Fuse in this TV receiver is blown replace it with the FUSE specified in the Replacement Parts List 3 When replacing a high wattage resistor oxide metal film resistor in circuit board keep the resistor 10 mm away from cir...

Page 11: ...Service manual CP 795 10 ...

Page 12: ... Microcontroller configuration Option 4 3 2 White balance Select a dark picture and adjust Black G and Black R to the desired colour temperature Select a bright picture and adjust WP Red WP Green WP Blue to the desired colour temperature 4 3 3 Focus Adjust the Focus volume on FBT to have the best resolution on screen Option Tuner maker 0 DAEWOO SAMSUNG 1 DAEWOO SAMSUNG 2 SIEL 3 PHILIPS 4 3 TV setA...

Page 13: ...te for vertical distortion 4 3 5 Horizontal picture centering Adjust H Shift to have the picture in the center of the screen 4 3 6 East West correction Adjust the H Parall H Bow H Width EW Parabo Up Corner Dw Corner EW trapez to compensate for geometrical distortion H Parall EW Parabo H Bow Up Corner H Width Dw Corner ...

Page 14: ...Service manual CP 795 13 EW Trapez 4 3 7 AGC Adjust the antenna signal level at 68 dB V 2 Set RF AGC to 0 Increase RFAGC level and stop when the level on pin 6 of TDA936x goes below 2 5 Vdc ...

Page 15: ... 14 SCHEMATIC DIAGRAM ...

Page 16: ... 15 1 DTE 29G3ZZR 29G3KZR EXPLODED VIEW ...

Page 17: ... 16 PCB MAIN PRINTED CIRCUIT BOARD ...

Page 18: ...91050615 FLUX SOLDER DF 2012U 40 2291050301 FLUX SOLVENT IM 1000 90 2291051001 FLUX KILLER KFT 7 DF01 DSD50RH51B LED SD50 RH51BGRW DF01A 4853533600 HOLDER LED P P BK HPF01 4859102130 JACK EARPHONE YSC 1537 IF01 1TS0P1238W IC PREAMP TS0P1238WI1 JPF01 4859108450 JACK PIN BOARD YSC03P 4120 14A M381 4853816400 FRAME SUB PCB FR HIPS BK P603A 4850706S01 CONNECTOR YH025 06 YST025 ULW 200 P701A 4850703S18...

Page 19: ...C1 PTWBSW7410 CORD POWER ASS Y 906111 HOUSING TUBE 17700 PW000 4859906111 CORD POWER M5206 H03VVH2 F 2250 PW001 4857417700 TERM CLAMP PT 01 T3 Q401 PTS2SW4500 HEAT SINK ASS Y T2SW2499 7174300811 Q401 T2SD2499 TR 2SD2499 Q401A 4857024500 HEAT SINK AL EX B K Q401B 7174300811 SCREWTAPPTITE TT2 RND 3X8 MFZN R801 DPC7R0M290 POSISTOR 2322 662 96709 R802 RS02Y753JS R M OXIDE FILM 2W 75K OHM J SMALL R819 ...

Page 20: ...41 CEXF1H220V C ELECTRO 50V RSS 22MF 5X11 TP C542 CEXF1H100V C ELECTRO 50V RSS 10MF 5X11 TP C543 CEXF1H100V C ELECTRO 50V RSS 10MF 5X11 TP C550 CEXF1H229V C ELECTRO 50V RSS 2 2MF 5X11 TP C555 CEXF1C470V C ELECTRO 16V RSS 47MF 5X11 TP C560 CBXF1H104Z C CERA SEMI 50V F 0 1MF Z TAPPING C561 CEXF1E101V C ELECTRO 25V RSS 100MF 6 3X11 TP C564 CEXF1E101V C ELECTRO 25V RSS 100MF 6 3X11 TP C565 CBXF1H104Z ...

Page 21: ...5PXF1B471M FILTER EMI CFI 06 B 1H 470PF Z605 5PXF1B471M FILTER EMI CFI 06 B 1H 470PF Z606 5PXF1B471M FILTER EMI CFI 06 B 1H 470PF Z607 5PXF1B471M FILTER EMI CFI 06 B 1H 470PF Z608 5PXF1B471M FILTER EMI CFI 06 B 1H 470PF Z609 5PXF1B471M FILTER EMI CFI 06 B 1H 470PF Z610 5PXF1B471M FILTER EMI CFI 06 B 1H 470PF ZZ200 PTMPJAD416 PCB MAIN AXIAL AS DTE 29G3ZZR 10 2TM14006LB TAPE MASKING 3M 232 6 0X2000M...

Page 22: ... CERA 16VY5R 2200PF M AXIAL DA15 DUZ5R6BM DIODE ZENER UZ 5 6BM DA16 DUZ5R6BM DIODE ZENER UZ 5 6BM DA20 DUZ5R6BM DIODE ZENER UZ 5 6BM DA23 CBZR1C222M C CERA 16VY5R 2200PF M AXIAL DA24 CBZR1C222M C CERA 16VY5R 2200PF M AXIAL DA27 DUZ5R6BM DIODE ZENER UZ 5 6BM L101 5CPZ100K02 COIL PEAKING 10UH K AXIAL 3 5MM L350 5CPZ109M04 COIL PEAKING 1UH 10 5MM M LAL04TB L381 5CPZ109M04 COIL PEAKING 1UH 10 5MM M LA...

Page 23: ...RD AZ103J R CARBON FILM 1 6 10K OHM J R556 RD AZ562J R CARBON FILM 1 6 5 6K OHM J R567 RD AZ101J R CARBON FILM 1 6 100 OHM J R570 RD AZ102J R CARBON FILM 1 6 1K OHM J R580 RD AZ561J R CARBON FILM 1 6 560 OHM J R585 RD AZ224J R CARBON FILM 1 6 220K OHM J R586 RD AZ221J R CARBON FILM 1 6 220 OHM J R587 RD AZ101J R CARBON FILM 1 6 100 OHM J R588 RD AZ101J R CARBON FILM 1 6 100 OHM J R589 RD AZ101J R ...

Page 24: ... 1 6 15K OHM J R954 RD AZ223J R CARBON FILM 1 6 22K OHM J R955 RD AZ223J R CARBON FILM 1 6 22K OHM J R956 RD 2Z102J R CARBON FILM 1 2 1K OHM J R957 RD 2Z105J R CARBON FILM 1 2 1M OHM J RA01 RD AZ680J R CARBON FILM 1 6 68 OHM J RA02 RD AZ101J R CARBON FILM 1 6 100 OHM J RA03 RD AZ101J R CARBON FILM 1 6 100 OHM J RA04 RD AZ101J R CARBON FILM 1 6 100 OHM J RA05 RD AZ103J R CARBON FILM 1 6 10K OHM J R...

Page 25: ...686 AHYEON DONG MAPO GU SEOUL KOREA C P O BOX 8003 SEOUL KOREA TELEX DWELEC K28177 8 CABLE DAEWOOELEC E mail djkoo web dwe co kr TEL 82 2 360 7806 FAX 82 2 360 7877 ...

Page 26: ...rts of the screen can be chosen independently z Linear RGB or YUV input with fast blanking for external RGB YUV sources The Text OSD signals are internally supplied from the µ Controller Teletext decoder z Contrast reduction possibility during mixed mode of OSD and Text signals z Horizontal synchronisation with two control loops and alignment free horizontal oscillator z Vertical count down circui...

Page 27: ...lining underlining and italics z Soft colours using CLUT with 4096 colour palette z Globally selectable scan lines per row 9 10 13 16 and character matrix 12x10 12xl3 12x16 VxH z Fringing Shadow selectable from N S E W direction z Fringe colour selectable z Meshing of defined area z Contrast reduction of defined area z Cursor z Special Graphics Characters with two planes allowing four colours per ...

Page 28: ...WST VPS on line 16 of VBI Real time capture and decoding for WST Teletext in Hardware to enable optimised microprocessor throughput 10 pages stored On Chip lnventory of transmitted Teletext pages stored in the Transmitted Page Table TPT and Subtitle Page Table SPT Automatic detection of FASTEXT transmission Real time packet 26 engine in Hardware for processing accented G2 and G3 characters Signal ...

Page 29: ...Appendix Service manual CP 795 4 ...

Page 30: ...ian Germany West software version Spanish Dutch Belgium Spain Danish Finnish Italy Norwegian Swedish Switzerland Austria Denmark Finland Netherlands Norway Sweden Ireland Others DW9365 N1 3 BDx English Polish Poland Pan European not x is the Russian Hungarian Hungary Czech East Cyrillic software version Czech Slovakian rep Others Greek Romanian Greek TV processor version and Controller capacity IC...

Page 31: ...al drive B output VDRA 22 vertical driveA output IFIN1 23 IF input 1 IFIN2 24 IF input 2 IREF 25 reference current input VSC 26 vertical sawtooth capacitor TUNERAGC 27 tunerAGC output SIFIN1 28 SIF input 1 SIFIN2 29 SIF input 2 GND2 30 ground 2 for TV processor SIFAGC 31 AGC sound IF REF0 32 n u HOUT 33 horizontal output FBISO 34 flyback input sandcastle output QSS out 35 QSS intercarrier output E...

Page 32: ...amming supply VDDC 56 digital supply to core 3 3V OSCGND 57 oscillator ground supply XTALIN 58 crystal oscillator input XTALOUT 59 crystal oscillator output RESET 60 reset VDDP 61 digital supply to periphery 3 3V Audio Mute 62 Port 1 0 Audio mute output Push Pull Power 63 Port 1 1 Power output Push Pull IR in 64 Interrupt input 0 R C Infrared input ...

Page 33: ...Appendix Service manual CP 795 8 ...

Page 34: ...Section The MSP 3415D is designed to simultaneously perform digital demodulation and decoding of NICAM coded TV stereo sound as well as demodulation of FM or AM mono TV sound Alternatively two carrier FM systems according to the German terrestrial specs can be processed with the MSP 3415D The MSP 3415D facilitates profitable multistandard capability offering the following advantages Automatic Gain...

Page 35: ...y stereo sound is transmitted digitally The systems allow two high quality digital sound channels to be added to the already existing FM AM channel The sound coding follows the format of the so called Near Instantaneous Companding System NICAM 728 Transmission is performed using Differential Quadrature Phase Shift Keying DQPSK Table below offers an overview of the modulation parameters In the case...

Page 36: ...2 FM Mono NICAM PAL UK D K 6 5 6 2578125 D K1 6 5 6 7421875 D K2 6 5 5 85 D K NICAM FM Stereo FM Mono NICAM SECAM East USSR Hungary Architecture of MSP3415D Pin connections and short description Pin No Pin Name Type Short description 1 TP Out Test pin 2 NC Not Connected 3 NC Not Connected 4 TP Out Test pin 5 TP Out Test pin 6 ADR_SEL In I2C bus Address select 7 STANDBYQ In Standby Low active 8 NC ...

Page 37: ...2 right 34 SC2_OUT_L Out Scart Output 2 left 35 VREF1 Reference ground 1 high voltage part 36 SC1_OUT_R Out Scart output 1 right 37 SC1_OUT_L Out Scart output 1 left 38 NC Not Connected 39 AHVSUP Analog power supply 8 0V 40 CAPL_M Volume capacitor MAIN 41 AHVSS Analog ground 42 AGNDC Analog reference voltage high voltage part 43 NC Not Connected 44 NC Not Connected 45 NC Not Connected 46 NC Not Co...

Page 38: ...e TDA8944J comes in a 17 pin DIL power package Features Few external components Fixed gain Standby and mute mode No on off switching plops low standby current High supply voltage ripple rejection Outputs short circuit protected to ground supply and across the load Thermally protected Pin description Pin Symbol Description 1 OUT1 negative loudspeaker terminal 1 2 GND1 ground channel 1 3 Vcc1 supply...

Page 39: ... class G system Due to the full bridge output circuit the deflection coils can be DC coupled The IC is constructed in a Low Voltage DMOS process that combines Bipolar CMOS and DMOS devices MOS transistors are used in the output stage because of the absence of second breakdown 1 4 1 TDA8357J Features Few external components Highly efficient fully DC coupled vertical output bridge circuit Short rise...

Page 40: ...bol Description 1 Vi pos input voltage positive 2 Vi neg input voltage negative 3 Vp supply voltage 4 VOB output voltage B 5 GND ground 6 Vflb flyback supply voltage 7 VOA output voltage A 8 VO guard guard output voltage 9 VM input measuring resistor ...

Page 41: ...ink current from the diode modulator circuit Features Few external components Highly efficient fully DC coupled vertical output bridge circuit Short rise and fall time of the vertical flyback switch Guard circuit Temperature thermal protection High EMC because of common mode inputs East West output stage ...

Page 42: ...es Typical bandwidth of 5 5 MHz for an output signal of 60 Vpp High slew rate of 900V ms No external components required Very simple application Single supply voltage of 200V Internal reference voltage of 2 5 V Fixed gain of 50 Black current stabilisation BCS circuit Thermal protection Pin description Pin Symbol Description 1 Vi 1 inverting input 1 2 Vi 2 inverting input 2 3 Vi 3 inverting input 3...

Page 43: ...Output 6 SCL Serial clock 7 WC Write control 8 Vcc Supply voltage 4 Vss Ground The memory device is compatible with the I2C memory standard This is a two wire serial interface that uses a bi directionnal data bus and serial clock The memory carries a built in 4 bit unique device type identifier code 1010 in accordance with the I2C bus definition Serial Clock SCL The SCL input is used to strobe all...

Page 44: ...FET and control IC designed for flyback converter type switch mode power supply applications 1 7 2 Features Small SIP fully isolated molded 5 pins package Many protection functions Pulse by pulse overcurrent protection OCP Overvoltage protection with latch mode OVP Thermal protection with latch mode TSD 1 7 3 Block diagram ...

Page 45: ...e TOFF max 45 55 µSEC Minimum time for input of quaxi resonant signals 1 5 TTH 2 1 0 µSEC Minimum off time TOFF min 1 5 µSEC O C P F B terminal threshold voltage 1 1 5 VTH 1 0 68 0 73 0 78 V O C P F B terminal threshold voltage 2 1 5 VTH 2 1 3 1 45 1 6 V O C P F B terminal extraction current 1 2 IOCP FB 1 2 1 35 1 5 mA OVP operation voltage 4 5 VIN OVP 20 5 22 5 24 5 V Latch circuit sustaining vol...

Page 46: ...Appendix Service manual CP 795 21 2 Circuit description 2 1 Block diagram ...

Page 47: ...gh performance hi fi stereo sound processing can be achieved Video switches The video switch has one input for an external CVBS or Y C signal The selected CVBS signal can be supplied to pin 38 the IF video output The selection between both signals is realised by the controlling software in subaddress 22H The video ident circuit is connected to the selected signal This ident circuit is independent ...

Page 48: ...er The ICs can decode PAL NTSC and SECAM signals The PAL NTSC decoder does not need external reference crystals but has an internal clock generator which is stabilised to the required frequency by using the 12 MHz clock signal from the reference oscillator of the µ Controller Teletext decoder The Automatic Colour Limiting ACL circuit switchable via the ACL bit in subaddress 2OH prevents that overs...

Page 49: ...trol circuit The output signal has an amplitude of about 2 Volts black to white at nominal input signals and nominal settings of the various controls To obtain an accurate biasing of the picture tube the Continuous Cathode Calibration system has been included in these ICs A black level off set can be made with respect to the level which is generated by the black current stabilisation system In thi...

Page 50: ...ation TV IF audio filter with two channels Channel 1 L with one pass band for sound carrier at 40 40 MHz Channel 2 L D K I B G with one pass band for sound carriers between 32 40 MHz and 33 40 MHz For SECAM L and L the TDA936x is switched to positive modulation via I2C bus SECAM L only occur in VHF band I and have their picture and sound carrier interchanged compared to SECAM L and PAL B G channel...

Page 51: ...Appendix Service manual CP 795 26 Chassis block diagram IF ...

Page 52: ...nding on Q508 base level External SVHS from SCART 2 The sound source switching is done in the MSP3415D I601 by the µ Controller via I2C bus Fast R G B insertion The external R G B insertion needs a fast switching and cannot be controlled by the software instruction cycle of 1µ sec The fast switching pin 16 of SCART 1 is directly connected to the TV processor pin 45 Fast blanking input The display ...

Page 53: ...input only operation of the port Special port for LED Pin 11 has the same functionality as the general I O pins but in addition their current source and sink capacity is 8 mA instead of 4 mA These pins are used for driving LED s via a series current limiting resistor Controller I O pin configuration and function table pin name description 2 5 Sound processing Analogue sound IF input section The in...

Page 54: ...ecoder When the set is in Auto detection mode default mode after ATSS the controlling software set automatically the sound mode NICAM mono NICAM Dual 1 or NICAM Dual 2 depending on the transmitted mode In case of 2 Carrier FM transmission the controlling software read the transmission mode and the signal quality level from the Stereo Detection Register When the set is in Auto detection mode the co...

Page 55: ...Appendix Service manual CP 795 30 Sound signal flow diagram ...

Page 56: ...lifier is operating normally The operating mode is activated at VMODE 0 5 V 2 7 Vertical deflection The vertical driver circuit is a bridge configuration The deflection coil is connected between the output amplifiers which are driven in phase opposition The differential input circuit is voltage driven The input circuit is especially intended for direct connection to driver circuits which deliver s...

Page 57: ...a damping resistor R305 is connected across the deflection coil EAST WEST Amplifier TDA8358J only The East West amplifier is current driven It can only sink currents of the diode modulator circuit A feedback resistor R397 is connected between the input and output of this inverting amplifier in order to convert the East West correction input into an output voltage ...

Page 58: ...ol IC designed for flyback converter type switch mode power supply applications 2 8 2Power supply primary part operations An oscillator generates pulses signals which turn on and off a MOSFET transistor 2 8 2 1 Start up circuit VIN The start up circuit is used to start and stop the operation of the control IC by detecting a voltage appearing at VIN pin pin 4 ...

Page 59: ...ltage does not increase to the set voltage immediately after the control circuit starts operating VIN starts dropping However as this winding voltage reaches the set value before VIN voltage drops to the shutdown voltage at 11V the control circuit continues operating see below VIN voltage at start up R805 resistor prevents that VIN pin voltage varies according to the secondary side output current ...

Page 60: ...Appendix Service manual CP 795 35 2 8 2 1 STR F6653 oscillating operation ...

Page 61: ...etermined by C1 and R1 is the OFF time of the MOSFET F When C1 voltage falls to around 3 7V the STR F6653 internal oscillator is reversed again and the MOSFET turns ON C1 is quickly charged to around 6 5V The MOSFET continues to oscillate by repeating the above procedure 2 8 2 3 STR F6653 protection circuits overcurrent protection function OCP Overcurrent protection is performed pulse by pulse det...

Page 62: ...ntroller power supply pins pins 54 56 61 and to the reset pulse circuit which provides reset pulse to I501 microcontroller reset pin pin 60 Then the microcontroller starts its initialization Its power pin pin 63 is set to high which allows delivery of power supply voltages 123V 8V 5V At this step all IC s start working but no picture appears on screen I501 IC doesn t provide horizontal drive volta...

Page 63: ... pulse circuit 2 9 1 4 Reset pulse circuit operations description When DC supply voltage from I823 regulator starts rising from 0V to 1 2V no current flows through D591 zener diode So Q510 is in off mode Also Vbe Q511 Vcc 2 Vcc Vcc 2 0 6V So Q511 is in off mode Then no voltage reaches I501 pin 60 When this voltage reaches 1 2 V Q510 stays in off mode but Vbe Q511 0 6V So Q511 is switched on and st...

Page 64: ...tely Q511 starts conducting pulling I501 pin 60 high At the same time it discharges the reset capacitor C501 Discharging this capacitor is necessary to garantee a defined reset pulse duration 2 9 2 TV normal run and stand by mode operations Depending on remote control commands I501 microcontroller part pin 63 power is set to high for normal run mode low for stand by mode 2 9 2 1 TV on normal run m...

Page 65: ...the ground and I810 controlled rectifier gate pin is set to low no conducting So current from 11V DC voltage from T801 SMPS transformer pin 13 does not flow through Q811 and Q810 transistors but flows through I806 IC error amplifier Q809 is conducting So Q810 is not conducting and no current flows from Q810 collector to the ground Therefore the power circuit diagram is the following one 2 9 2 1 2 ...

Page 66: ... required on this line 143V supply voltage line includes an IC error amplifier I806 which corrects unexpected DC voltage variations on this line 2 9 2 1 4 power supply IC delivery during TV set normal run power supply line IC power supply delivery Remarks 143V FBT FBT supplies 45V to I301 vertical IC FBT supplies 45V to T401 H drive FBT supplies 14V to I301 vertical IC FBT supplies 33V to the tune...

Page 67: ...Appendix Service manual CP 795 42 2 9 2 2 TV set on stand by mode 2 9 2 2 1 TV set circuit diagram on stand by mode ...

Page 68: ... flows from pin 16 SMPS transformer to the ground via I804 photo coupler and Q810 and Q811 transistors which are conducting In these conditions I801 delivers pulses on light mode and T801 produces voltages with reduced power As I810 is conducting current flows also from pin 16 SMPS transformer to I823 3 3V regulator for I501 µcom IR receiver and front mask buttons supply voltage then remote contro...

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