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PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY, SUBJECT : X-RADIATION NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFAC- 1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PER- TURER’S APPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLY SONNEL COVER THE SUBJECT OF X-RADIATION.
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SERVICING PRECAUTIONS CAUTION : Before servicing the DVD covered by this service Electrostatically Sensitive (ES) Devices data and its supplements and addends, read and follow the Some semiconductor (solid state) devices can be damaged SAFETY PRECAUTIONS. NOTE : if unforeseen circum- easily by static electricity.
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SECTION 2 CABINET & MAIN CHASSIS CONTENTS 1. EXPLODED VIEWS ........................2-2 1. Cabinet and Main Frame Section ...................2-2 2. Deck Mechanism Section......................2-4 3. Packing Accessory Section ....................2-5...
SECTION 3 ELECTRICAL CONTENTS ELECTRICAL TROUBLESHOOTING GUIDE ..............3-2 1. Power check flow........................3-2 2. System operation flow ......................3-3 3. Test & debug flow ........................3-4 4. Karaoke flow ..........................3-10 DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING ....3-11 1. SYSTEM 27MHz CLOCK,RESET,FLASH R/W SIGNAL............3-11 2.
ELECTRICAL TROUBLESHOOTING GUIDE 1. Power check flow No VF+ No 5V_A . Is 5.2VA section working? Is 5.2VA section working? Is 5.2V present at emitter Check F102 No 5.2VA. of Q107? Replace D109. Check F101 Replace Q107. Is there a DC voltage at Replace R101.
2. System operation flow Power On 1. 8032 initializes SERVO, DSP & RISC registers 2. Write RISC code to SDRAM 3. Reset RISC Show LOGO Tray Closed? Tray Close to Closed position SLED at Inner Side? SLED Moves to Inner Position 1.
3. Test & debug flow TEST Check the AC Vol tage Check the POWER PART Power PCBA (110V or 220V) Switch on the Power PCBA the DC Vol tage outputs OK? Check the POWER PART (5V, 3.3V, 8V, 12V) Make sure the main PCBA don’t Is 3.3V and 2.5V DC Check the regulators or diode( D670).
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RESET or Power On. Flash Check connecti on lines between FLASH Memory operates Show LOGO? & MT1379 and the FLASH access time properly? whether is sui table or not. Check connection lines between SDRAM SDRAM(IC502,IC503) & MT1379 and the works properl y? SDRAM is damaged.
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Does the SLED move Check the connection line of Motor Driver STBY to inner side when it is at STBY signal . Pin is High? outter positi on? Check the rel ated circuit of Motor Driver STBY FMSO. Pin is High? Check the amp circuit on SL+ and SL- output motor driver.
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Check the laser power circuit Laser turns on when LD01 or LD02 output on MT1336 and connecting to reading disc? properly? power transistor. (Q204, Q205) Collector Check therel ated ci rcuit on voltage of power laser power transi stor transistor is OK? ( Q204, Q205) Check cable connection between transistor couput and pick-up head.
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Proper Check connections between signals on A, B, C, Focus ON OK? MT1336 and pick-up head. D of MT1336 Check the related circuit Proper FEO signal on MT1336 FEO sugnal . on MT1336? Check FEO connection between MT1336 and MT1379 Check the related Proper FEO signal Track On OK?
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Audio Normal DAC received Check connection between MT1379 Audio output & Audio DAC. (Check VRST#, ACLK, correct data stream? when disc playback? ABCK, ASDAT3) Normal Check the related circuit of Audio DAC Audio DAC. (Check Audio out? (IC601) out Pin 14, 15,18,19) Check Audio filter, amplify, mute circuit.
4. KARAOKE Flow (KARAOKE MODEL ONLY) Start Insert the Mic jack Is the Mic signal at the IC801 pin3. Is the Mic signal at the IC801 Pin 2. Is the Digital Replace IC801. signal output at the Replace the IC5K1. IC5K1 Pin1.
DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING 1. SYSTEM 27MHz CLOCK,RESET,FLASH R/W SIGNAL 1) MT1379 main clock is at 27MHz(X501) 3.8V, 27MHz FIG 1-1 2) MT1379 & MT1336 reset is high active. Power Cord in 5.2VA PWR_CTL(CN505 PIN 7) M_RESET(CN505 PIN 9) URST(IC501 PIN 188) FIG 1-2...
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3) RS232 waveform during procedure(Downloading) TXD(J6 PIN3) RXD(J6 PIN 2) FIG 1-3 4) Flash R/W enable signal during download(Downloading) FRD(IC5A1 PIN 28) FWR(IC5A1 PIN 11) FIG 1-4 3-12...
6. KARAOKE Block Diagram(KARAOKE MODEL ONLY) Microphone AUDIO AUDIO Signal MPEG Microphone1 PREAMP (KA741) (MT1379) (CS5331) (CS4391) (BA3308) (Block Digram) 1 The unit turns to KARAOKE MODE with ou-screen lyrics display and melody sound when it play backs VCD or DVD KARAOKE DISC. 2.
CIRCUIT DIAGRAMS IMPORTANT SAFETY NOTICE CUIT. SPECIAL COMPONENTS ARE SHADED ON THE NOTE : SCHEMATIC FOR EASY IDENTIFICATION. 1. Shaded( ) parts are critical for safety. Replace only WHEN SERVICING THIS CHASSIS, UNDER NO CIR- THIS CIRCUIT DIAGRAM MAY OCCASIONALLY DIF- with specified part number.
2. SYSTEM CIRCUIT DIAGRAM No Power on Video signal not appeared AUDIO DAC interface VIDEO interface RF & MOTOR DRIVE interface System not working or screen is abnormal System not working or Digitron not display System not operate Digitron all not display Program download fail System not working Video signal Y...
4. TIMER, 5.1CH, SCART, KARAOKE CIRCUIT DIAGRAM Power LED abnormal (OPTIONAL PART) Karaoke not operate. Remocon not operate System not operate System not operate or Digitron abnormal or Digital abnormal Key not operate. (OPTIONAL PART) (OPTIONAL PART) 5.1CH Audio Bad '02.
5. AV/JACK CIRCUIT DIAGRAM All Video signal isn't appear or bad 2CH Audio out bad. SACD OPTION 2.5V doesn't appeat System not working 2CH Audio out bad. Video Signal Y Video Signal CVBS '02. 12. 26 R14602A Video Signal Color 2CH Audio 3-39 3-40...
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Q201 Q202 Q203 Q204 Q205 IC201 IC202 IC501 IC502 IC505 IC510 IC5A1 IC5K1 IC601 IC602 IC604 (MT1336E) (MOTOR) (MT1379) (SDRAM) (EEPROM) (BUFFER) (FLASH) (KARAOKE) (CS4391) (AMP) (MM1623XFBE) STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY PIN STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY STOP PLAY 5.14 4.34...
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