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1、MICRO COMPONENT SYSTEM SERVICE MANUAL MODEL: LX-U250A, LXS-U250 SERVICE MANUAL MODEL: LX-U250A, LXS-U250 RadioFans.CN 收音机爱 好者资料库 - 1-1 - CONTENTS SECTION 1. GENERAL SERVICING PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 ESD PRECAUTIONS
2、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5 SECTION 2. ELECTRICAL TROUBLESHOOTING GUIDE . . . . . . . .
3、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 WAVEFORMS OF MAKOR CHECK POINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10 INTERNAL BLOCK DIAGRAM of ICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4、 2-22 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-29 SCHEMATIC DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-33 WIRING DIAGRAM . . . . . . . . . . . . . .
5、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-45 PRINTED CIRCUIT DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-47 SECTION 3. EXPLODED VIEWS CABINET AND MAIN FRAME SECTION . . . . . . . . . . . . . . . . . . . . .
6、. . . . . . . . . . . . . . . . . .3-1 SINGLE DECK MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3 CD MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-5 SECTION 4.
7、 SPEAKER SECTION MODEL: LXS-U250, LXS-W250 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1 SECTION 5. REPLACEMENT PARTS LIST REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1 Radi
8、oFans.CN 收音机爱 好者资料库 - 1-2 - SERVICING PRECAUTIONS NOTES REGARDING HANDLING OF THE PICK-UP 1. Notes for transport and storage 1) The pick-up should always be left in its conductive bag until immediately prior to use. 2) The pick-up should never be subjected to external pressure or impact. 2. Repair n
9、otes 1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic materials. 2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure and impact. If it is subjected to strong pressure or impact, the result may be an oper
10、ational malfunction and/or damage to the printed-circuit board. 3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that reason the adjustment point and installation screws should absolutely never be touched. 4) Laser beams may damage the eyes! Absolutel
11、y never permit laser beams to enter the eyes! Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged. 5) Cleaning the lens surface If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as used for camera lens).T
12、he lens is held by a delicate spring. When cleaning the lens surface, therefore, a cotton swab should be used, taking care not to distort this. 6) Never attempt to disassemble the pick-up. Spring by excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do not
13、use any other liquid cleaners, because they will damage the lens.) Take care not to use too much of this alcohol on the swab, and do not allow the alcohol to get inside the pick-up. Storage in conductive bagDrop impact NEVER look directly at the laser beam, and dont let contact fingers or other expo
14、sed skin. Magnet How to hold the pick-up Conductive Sheet Cotton swab Pressure Pressure SECTION 1. GENERAL RadioFans.CN 收音机爱 好者资料库 - 1-3 - NOTES REGARDING COMPACT DISC PLAYER REPAIRS 1. Preparations 1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode).These compo
15、nents are sensitive to, and easily affected by, static electricity. If such static electricity is high voltage, components can be damaged, and for that reason components should be handled with care. 2) The pick-up is composed of many optical components and other high-precision components. Care must
16、be taken, therefore, to avoid repair or storage where the temperature of humidity is high, where strong magnet- ism is present, or where there is excessive dust. 2. Notes for repair 1) Before replacing a component part, first disconnect the power supply lead wire from the unit 2) All equipment, meas
17、uring instruments and tools must be grounded. 3) The workbench should be covered with a conductive sheet and grounded. When removing the laser pick-up from its conductive bag, do not place the pick-up on the bag. (This is because there is the possibility of damage by static electricity.) 4) To preve
18、nt AC leakage, the metal part of the soldering iron should be grounded. 5) Workers should be grounded by an armband (1M ) 6) Care should be taken not to permit the laser pick-up to come in contact with clothing, in order to prevent sta- tic electricity changes in the clothing to escape from the armb
19、and. 7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin. CLEARING MALFUNCTION You can reset your unit to initial status if malfunction occur(button malfunction, display, etc.). Using a pointed good conductor(such as driver), simply short the RESET jump wire on t
20、he inside of the volume knob for more than 3 seconds. If you reset your unit, you must reenter all its settings(stations, clock, timer) NOTE: 1.To operate the RESET jump wire, pull the volume rotary knob and release it. 2. If you wish to operate the RESET jump wire, it is necessary to unplug the pow
21、er cord. Resistor (1 Mohm) Conductive Sheet Resistor (1 Mohm) Armband RESET jump wire VOLUME VOLUME KNOB DOWN UP - 1-4 - ESD PRECAUTIONS Electrostatically Sensitive Devices (ESD) Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called
22、 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. Immediatel
23、y 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 reas
24、ons 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 sur- face such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly. 3. Use only a grounded-tip soldering iron t
25、o 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
26、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
27、. 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 PR
28、ECAUTIONS. 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 gen- erate static electricity sufficient to damage an ESD device). CAUTION. GRA
29、PHIC 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 EQUILATERA
30、L TRIANGLE IS INTENDED TO ALERT THE SERVICE PER- SONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE. - 1-5 - SPECIFICATIONS NOTE : Specification are subject to change without notice in the course of product improvement. - 1-6 - - 2-1 - CD PART TROUBLESHOOTING GUIDE SECTION
31、2. ELECTRICAL TURN ON CD OPEN CLOSE CHECK “ READING ” DISPLAY CHECK READING OK CHECK IF PLAY, AUDIO OUTPUT CHECK OK CONNECTOR CHECK (PN806) CHECK LC78690W (IC801) CHECK AM5810FP (IC802) CHECK PICKUP MOVEMENT CONNECTOR CHECK(PN801,PN802) CHECK MICOM INTERFACE CIRCUIT( PN805 ) CONNECTOR CHECK ( PN802,
32、 PN804, PN806 ) CHECK MICOM INTERFACE CIRCUIT( PN805 ) CHECK POWER SUPPLY CIRCUIT( PN806 ) CONNECTOR CHECK ( PN804, PN806 ) - 2-2 - OPEN CLOSE NG CONNECTOR LOCKING CHECK ( PN804 ) CHECK POWER SUPPLY CIRCUIT( PN805, PN806) PN 806 PIN 4 = 12V, PIN 5 = 6.2V PN805 PIN 1 = 5V CHECK VOLTAGE CHANGE OF OPEN
33、 CLOSE , AND IC802 INPUT VOLTAGE PIN 7, 8, 20 (=6.2V) (PN805 PIN 2:BTL_MUTE, 14:OPEN 15:CLOSE) DEFECTIVE MAIN POEWR SUPPLY DEFECTIVE MICOM DEFECTIVE MECHANISM - 2-3 - “ READING ” DISPLAY CHECK (= ONLY “CD “DISPLAY) CONNECTOR LOCKING CHECK (PN802, PN804,PN805,PN806 ) DEFECTIVE CONNECTOR OR MAIN POWER
34、 SUPPLAY DEFECTIVE IC804 DEFECTIVE MICOM OR CONNECTOR DEFECTIVE MICOM OR CONNECTOR DEFECTIVE IC801 CHECK VOLTAGE THE PIN 2 OF IC804 IC804 PIN 2 :3.3V CHECK RESET SIGNAL OF PN805 PN805 PIN 4 :3V CHECK POWER SUPPLY PORT( PN805 ,PN806) PN 806 PIN 4 = 12V, PIN 5 = 6.2V PN805 PIN 12 = 5V CHECK MICOM INTE
35、RFACE CIRCUIT( PN805 ) PN805 PIN 3,4,5,6,7,8,9 SIGNAL CHECK (3:WRQ, 4 :RESET 5 :DO, 6:DI, 7 :CL 8:CE, 9:FSEQ) CHECK THE WAVE FORM #1 - 2-4 - READING OK CHECK (= “NO DISC” DISPLAY) CONNECTOR LOCKING CHECK(PN801,PN802) DOES SLED MOVE ? DOES LENSE MOVE ? (= UP & DOWN) CHECK PN802 PIN 3,4( SL+,SL-) A B
36、C D E CHECK PN801 PIN 13,16( FA-, FA+) CHECK PN801 PIN 10( LD ) CHECK PN802 PIN 5,6( SP+,SP-) CHECK PN801 PIN 14,15 (TA-, TA+) DEFECTIVE PICKUP OR IC802 OR IC801 DEFECTIVE PICKUP OR IC801 DEFECTIVE PICKUP OR IC802 OR IC801 DEFECTIVE PICKUP OR IC802 OR IC801 DEFECTIVE PICKUP OR IC802OR IC801 DOES LAS
37、ER LIGHT ? DOES SPINDLE ROTATE ? IS READING OK ? - 2-5 - READING OK CHECK #A (= “NO DISC” DISPLAY) A DOES SL+ WAVEFORM APPEAR AT ( IC802 PIN 13 AND PN 802 PIN 3) WAVEFORM #2 SLED MOTOR WAVE DOES SLIN WAVEFORM APPEAR AT ( IC802 PIN 5) WAVEFORM #2 SLED DRIVE WAVE CHECK PN802 CONNECTOR LINE DEFECTIVE I
38、C801 DEFECTIVE IC802 DEFECTIVE PN802 CONNECTOR DEFECTIVE PICKUP SLED MOTOR - 2-6 - READING OK CHECK #B (= “NO DISC” DISPLAY) B DOES FA+ WAVEFORM APPEAR AT ( IC802 PIN 16 AND PN801 PIN 13) WAVEFORM #3 FOCUS COIL DRIVE WAVE DOES FAIN- WAVEFORM APPEAR AT ( IC802 PIN 25) WAVEFORM #3 FOCUS DRIVE WAVE CHE
39、CK PN801 CONNECTOR LINE DEFECTIVE IC801 DEFECTIVE IC802 DEFECTIVE PN801 CONNECTOR DEFECTIVE PICKUP FOCUS ACTUATOR - 2-7 - READING OK CHECK #C (= “NO DISC” DISPLAY) C IS ?V APPLIED TO PIN10 OF PN501 LASER SUPPLY VOLTAGE CHECK CHECK PN801 CONNECTOR LINE IS 3.3 V APPLIED TO PIN30,36,39,41,61,68,75 OF I
40、C801 RF IC SUPPLY VOLTAGE CHECK IS 2.3 V PIN18 OF IC801 LASER CONTROL VOLTAGE CHECK DEFECTIVE IC804 DEFECTIVE IC801 DEFECTIVE Q801 OR D801 DEFECTIVE PN801 CONNECTOR DEFECTIVE PICKUP LASER PART - 2-8 - READING OK CHECK #D (= “NO DISC” DISPLAY) D DOES SP+ WAVEFORM APPEAR AT ( IC802 PIN 11 AND PN802 PI
41、N 5) WAVEFORM #4 SPINDLE MOTOR DRIVE WAVE DOES SPIN WAVEFORM APPEAR AT ( IC802 PIN 6) WAVEFORM #4 SPINDLE DRIVE WAVE CHECK PN802 CONNECTOR LINE DEFECTIVE IC801 DEFECTIVE IC802 DEFECTIVE PICKUP SPINDLE MOTOR DEFECTIVE PN802 CONNECTOR - 2-9 - READING OK CHECK #E (= “NO DISC” DISPLAY) E DOES TA+ WAVEFO
42、RM APPEAR AT ( IC802 PIN 17 AND PN801 PIN 14) WAVEFORM #5 TRACKING COIL DRIVE WAVE CHECK PN802 CONNECTOR LINE DEFECTIVE IC801 DEFECTIVE IC802 DEFECTIVE PN802 CONNECTOR DEFECTIVE PICKUP OR IC801 DEFECTIVE PICKUP OR IC801 DOES ARF SIGNAL APPEAR? (IC801 PIN 2 ) WAVEFORM #6 DOES FE, TE SIGNAL APPEAR? (I
43、C801 PORT FE:10, TE:16) WAVEFORM #6 DOES TAIN- WAVEFORM APPEAR AT ( IC802 PIN 22) WAVEFORM #5 TRACKING DRIVE WAVE - 2-10 - #1. MICOM INTERFACE WAVEFORM (PN805 PIN 3, 4, 5, 6) during power on PIN 6 : DI PIN 5 : DO PIN 4 : RESET PIN 3 : WRQ #1. MICOM INTERFACE WAVEFORM (PN805 PIN 3, 4, 5, 6) during no
44、rmal play PIN 6 : DI PIN 5 : DO PIN 4 : RESET PIN 3 : WRQ #1. MICOM INTERFACE WAVEFORM (PN805 PIN 7, 8, 9) during power on PIN 9 : FSEQ PIN 8 : CE PIN 7 : CL #1. MICOM INTERFACE WAVEFORM (PN805 PIN 7, 8, 9) during normal play PIN 9 : FSEQ PIN 8 : CE PIN 7 : CL WAVEFORMS OF MAKOR CHECK POINT - 2-11 -
45、 #2. SLED DRIVE AND MOTOR WAVEFORM (IC802 PIN 5, 13) when focus search #3. FOCUS DRIVE AND MOTOR WAVEFORM #3. FOCUS DRIVE AND MOTOR WAVEFORM (IC802 PIN 25, IC802 PIN 16) (IC802 PIN 25, IC802 PIN 16) When focus search failed or there is no disc on trayThere is disc on tray and focus search success PI
46、N 5 : SLIN PIN 13 : SL+ PIN 25 : FAO PIN 16 : FA+ #2. SLED DRIVE AND MOTOR WAVEFORM (IC802 PIN 5, 13) during normal play PIN 5 : SLIN PIN 13 : SL+ PIN 25 : FAO PIN 16 : FA+ - 2-12 - #5. TRACK DRIVE AND MOTOR WAVEFORM (IC802 PIN 22 , IC802 PIN 17) during normal play #4. SPINDLE DRIVE AND MOTOR WAVEFO
47、RM (IC802 PIN 6, 11) when TOC reading PIN 6 : SPIN PIN 11 : SP+ PIN 22 : TAO PIN 17 : TA+ #6. RF, FOCUS AND TRACKING ERROR WAVEFORM (IC801 PIN 2, 10, 16) during normal play PIN 2 : RFOUT PIN 10 : FE PIN 16 : TE - 2-13 - USB PART TURN ON USB “CHECKING ”OR “USB”DISPLAY CHECK READING OK CHECK OK CONNEC
48、TOR CHECK ( PN805, PN806, PN810 ) CHECK POWER SUPPLY CIRCUIT( PN806 ) CHECK MICOM INTERFACE CIRCUIT( PN805 ) CHECK PN810 1 PIN :5V CHECK PN810 PIN 2(D-), 3(D+) CHECK OTI6888 (IC805) CHECK LC78690W (IC801) CONNECTOR CHECK (PN806) IF PLAY, AUDIO OUTPUT CHECK - 2-14 - VKK CHECK P-SENS CHECK PN301 3Pin
49、DC -27V CHECK OK ZD900 (+)VOLTAGE CHECK (5V) IC301 26PIN PATTERN CHECK ZD901 (-)-27V CHECK D912(+)WAVE CHECK D912 CHANGE YES YES NO NO YES Q900 TURN ON CHECK C921(-)-27V UNDER VOLT CHECK YES NO D907,D906 CHANGE OK VOLTAGE CHECK LIST YES NO Q900 CHANGE YES NO - 2-15 - VOLTAGE CHECK ALL Fuse CHECK IC901,IC902 INPUT DC VOLT CHECK C904(+),C905(-)DC VOLT OUTPUT CHECK D700 CHANGE TransformerCHANGE IC301 Troubleshooting CHECK MUTE YES FUSE CHANGE CN900 (-)1,2 PIN,(+)5,6 PIN OUTPUT VOLTAGE,D900 CHECK YES NO YES NO NO IC903 Output DC V
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