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SERVICE MANUAL MODEL : LAC-M1600(R)
DETACHABLE FRONT PANEL CAR CD RECEIVER SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT, READ THE "SAFETY PRECAUTIONS" IN THIS MANUAL.
MODEL : LAC-M1600(R)
[CONTENTS]
SECTION 1. GENERAL
· SERVICING PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 · ESD PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 · SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
SECTION 2. ELECTRICAL
· ELECTRICAL TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 · WAVEFORMS OF MAJOR CHECK POINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6 · INTERNAL BLOCK DIAGRAM OF ICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7 · BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14 · SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16 · PRINTED CIRCUIT DIARGAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
SECTION 3. EXPLODED VIEWS
· CABINET AND MAIN FRAME SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 · MECHANISM (PICK-UP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
SECTION 4. REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
- 1-1 -
SECTION 1. SUMMARY
SERVICING PRECAUTIONS
Always disconnect the power source before:
1) Removing or reinstalling any component, circuit board, module or any other instrument assembly. 2) Disconnecting or reconnecting any instrument electrical plug or other electrical connection. 3) Connecting a test substitute in parallel with an electrolytic capacitor in the instrument. CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard.
Do not defeat any plug/socket B+ voltage interlocks with which instruments covered by
this service manual might be equipped.
Do not apply power to this instrument and or any of its electrical assemblies unless all
solid-state device heat sinks are correctly installed.
Always connect a test instrument's ground lead to the instrument chassis ground before
connecting the test instrument positive lead. Always remove the test instrument ground lead last.
1) The service precautions are indicated or printed on the cabinet, chassis or components. When servicing, follow the printed or indicated service precautions and service materials. 2) The Components used in the unit have a specified conflammability and dielectric strength. When replacing any components, use components which have the same ratings. Components marked in the circuit diagram are important for safety or for the characteristics of the unit. Always replace with the exact components. 3) An insulation tube or tape is sometimes used and some components are raised above the printed writing board for safety. The internal wiring is sometimes clamped to prevent contact with heating components. Install them as they were. 4) After servicing always check that the removed screws, components and wiring have been installed correctly and that the portion around the service part has not been damaged. Further check the insulation between the blades of attachment plug and accessible conductive parts.
- 1-2 -
ESD PRECAUTIONS
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated circuits and some field-effect transistors and semiconductor chip components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity. 1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed for potential shock reasons prior to applying power to the unit under test. 2. After removing an electrical assembly equipped with ESD devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly. 3. Use only a grounded-tip soldering iron to solder or unsolder ESD devices. 4. Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges sufficient to damage ESD devices. 5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD devices. 6. Do not remove a replacement ESD device from its protective package until immediately before you are ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive materials). 7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the protective material to the chassis or circuit assembly into which the device will by installed. CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER SAFETY PRECAUTIONS. 8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ESD device).
CAUTION. GRAPHIC SYMBOLS
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED "DANGEROUS VOLTAGE" THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.
- 1-3 -
SPECIFICATIONS
1. GENERAL Power requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DC12V~15V Ground system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Negative Dimensions(W x H x D) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 x 58 x 166mm Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Net: 1.3kg 2. RADIO SECTION Frequency range Intermediate frequency Usable sensitivity Signal to noise ratio 3. COMPACT DISC SECTION Frequency response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Hz~20kHz Channel separation (Line out) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90dB (1kHz) Signal to noise ratio (Line out) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110dB 4. AUDIO SECTION Maximum output power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50W x 4 Speaker impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 x 4 or 8 x 4 NOTE: The design and specifications are subject to change without notice in the sourse of product improvement. FM 65.0~74.0MHz(Optional), 87.5~108MHz 10.8MHz 10dBµV 55dB AM(MW) 522~1,620kHz (Optional:530~1,710kHz/ 520~1,620kHz) 450kHz 28dBµV 45dB
- 1-4 -
SECTION 2. ELECTRICAL
ELECTRICAL TROUBLESHOOTING GUIDE
1. No Power.
Any Key power on.
YES NO Is power turnd on? Check power supply circuitry. Q930, Q924, Q919, Q920, Q921, IC902, pin1
YES NO DISC loading? Check loading supply circuitry. Q9001, Q902, Q903, Q904, PN503, IC507, IC506, IC508
YES NO Does initial reading occur?
Check laser circuitry. Q541, IC501 Check focusing circuitry. Q541, IC501
YES
Check DISC.
Can disc be played?
NO
Check tracking servo circuitry. Q541, IC501, IC503
YES NO Is audio output supplied? Check audio circuitry. IC501,IC509, CN503
YES OK
- 2-1 -
2. LCD light abnormal.
Any Key power on. (without DISC)
NO Do display LCD then light?
Check voltage in the power supply YES
NO Power supply circuitry defective. Q371,Q372,IC403
Is u-com IC906 LCD reset circuit normal?Pin74
NO
· Reset circuit defective. IC901 Surrounding circuit defective.
YES Is u-com IC906 X1,X2 terminal Pin11,12,14,15 input? OSC :19.2MHz OSC :32.768kHz YES Is u-com IC906 keyin Pin19,20 5volt input? YES NO NO Q921,ZD910 PCB pattern defective.
NO
X101,X102,C101, C102,C103,C104.
Is u-com IC401 Pin75, 76, 78 output waveform normal?
IC906,Pin74,75,76 front PCB pattern defective.
YES NO
Is IC901 Com1, Com2, Com3 output waveform normal?
IC901,Surrounding circuit PCB pattern defective.
YES Display LCD connector defective.
- 2-2 -
3. Initial reading is not carried out.
Slide motor moves (With disc) YES NO Spindle motor turns WAVEFORM #1 YES (with disc) Does RF waveform appear? IC501 Pin49 WAVEFORM #2 NO Check the Voltage change of CN503 Pin12 (6.4~6.8V)
YES
NO NO
Defective connector CN503 Defective IC501 Defective connector CN503 Defective MICOM
Check the Voltage IC501 Pin23 (1.4V~1.8V)
YES
Check the Data transmission from CN503 (16, 17, 18) to CD DSP WAVEFORM #5
YES
NO
Check the Data transmission from CN503 Pin21 to MICOM WAVEFORM #5
YES
Defective NO connector CN503 Defective IC503
Check the TRVP Voltage IC501 Pin23
YES
NO
Defective IC501
Check the change of SL +, SL - Voltage IC503 Pin13,14
YES
NO
Defective IC503
Laser light check A ?
YES
Defective contact CN501 Defective PICK-UP
Does FA+ waveform appear at IC501 Pin23? WAVEFORM #3 focus coil drive wareform.
YES
NO
Does TE waveform appear at IC501 Pin24? WAVEFORM #4 TRACKING ERROR wareform
YES
NO
Is rotation normal?
NO
YES
Is there no dropout of RF signal?
YES
Defective IC501 Defective PICK-UP
- 2-3 -
A When laser does not light.
Is "2.4V~3.4V" applied to pin42 of IC501? ( OV 3.4V 2.4V) NO NO NO Is data transferred from MICOM IC ? YES Defective MICOM or CN503.
Did pickup return to innermost circular? YES
Does voltage appear at IC503 Pin 13, 14?
NO Defective IC501.
YES
Defective slide motor and/or connector. (CN502)
Does it stop at inner pick circular after shift?
YES
Is defect output from LMT SW applied to Pin7 of PN503? OPEN CLOSE
NO
Defective LMT SW and/or connector. (CN502,CN503)
YES
YES
Defective MICOM.
NO Is power supplied to laser Q541? (Q541 collector: about 1.8V)
Defective IC501
- 2-4 -
B When laser light.
Laser lights YES Check the signal FOCUS SEARCH of IC501 Pin25 WAVEFORM #3 YES Check the signal of IC503 Pin 15, 16 WAVEFORM #3 YES Degraded laser diode Defective PICK-UP NO Defective IC501 NO
Defective IC501
C When SPINDLE motor dose not turn
Check the change for SPDO Voltage of IC501 Pin21 WAVEFORM #1 Check the change for SP +, SP -, Voltage of IC503 Pin11, 12 WAVEFORM #1 YES
NO Defective IC501
NO Defective IC503
Defective contact CN501 or Defective PICK-UP
- 2-5 -
WAVEFORMS OF MAJOR CHECK POINT
#1. SPINDLE DRIVE AND MOTOR WAVEFORM IC501(21), IC504(12) during TOC reading #2. RF WAVEFORM IC501(45), IC501(49) during TOC reading
#3. FOCUS DRIVE AND MOTOR WAVEFORM IC501(25), IC503(15) · When focus search failed or there is no disc on tray · There is disc on tray and focus search success
#4. TRACK DRIVE AND MOTOR WAVEFORM IC504(24), IC503(17) during TOC reading
- 2-6 -
INTERNAL BLOCK DIAGRAM OF ICs
I UPD78F0546(Micom) 1) Block Diagram
- 2-7 -
2) Pin Assignment
- 2-8 -
3) Pin Descriptions
- 2-9 -
- 2-10 -
I BD3805F 1) BLOCK DIAGRAM
- 2-11 -
I MN6627933CN(DSP) 1) Connection Diagram
- 2-12 -
I TA8275HQ 1) Block Diagram
- 2-13 -
BLOCK DIAGRAM
2-14
2-15
SCHEMATIC DIAGRAMS
· MAIN SCHEMATIC DIAGRAM
2-16
2-17
· MAIN-2 SCHEMATIC DIAGRAM
2-18
2-19
· FRONT SCHEMATIC DIAGRAM
2-20
2-21
· CD SCHEMATIC DIAGRAM
2-22
2-23
PRINTED CIRCUIT BOARD DIAGRAMS
· MAIN P.C. BOARD DIAGRAM
2-24
2-25
· FRONT P.C. BOARD DIAGRAM
· LCD LIGHTING P.C. BOARD DIAGRAM
2-26
2-27
· CD P.C. BOARD DIAGRAM
2-29
2-30
SECTION 3. EXPLODED VIEWS
CABINET AND MAIN FRAME SECTION
450
283 A50 A40 455 291 290 271 272 273 298 299 A42 294 297 296 295 293 A49 292 450 A43
268 263 453 *Accessory 835 A26 CABLE 818 450
454
A41 267
450 A46
450 451
274 254
255 256
456 454 450 266
457 257 251 253 252 270
250 264
265
3-1
3-2
MECHANISM (PICK-UP)
4
1
A03
5 1 3
2 2
3-3
3-4