LG-FE286E-cs-sm 电路图 维修手册.pdf

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1、3CD CHANGER HI-FI SYSTEM SERVICE MANUAL MODEL : FFH-286A/AD, FE-286E SERVICE MANUALMODEL:FFH-286A/AD, FE-286E RadioFans.CN 收音机爱 好者资料库 - 1-1 - CONTENTS SECTION 1. GENERAL SERVICING PRECAUTIONS.1-2 ESD PRECAUTIONS.1-4 SPECIFICATIONS.1-5 SECTION 2. ELECTRICAL ADJUSTMENTS.2-1 TROUBLESHOOTING.2-3 WAVEFOR

2、MS OF MAJOR CHECK POINT.2-7 BLOCK DIAGRAM.2-17 SCHEMATIC DIAGRAMS.2-19 WIRING DIAGRAM.2-27 PRINTED CIRCUIT DIARGAMS.2-29 INTERNAL BLOCK DIAGRAM OF ICs.2-38 REPAIRS REGARDING CD MECHANISM.2-45 SECTION 3. EXPLODED VIEWS CABINET AND MAIN FRAME SECTION .3-1 TAPE DECK MECHANISM: AUTO STOP DECK(OPTIONAL).

3、 3-3 TAPE DECK MECHANISM: AUTO REVERSE DECK.3-5 CD MECHANISM.3-7 SECTION 4. SPEAKER.4-1 SECTION 5. REPLACEMENT PARTS LIST.5-1 RadioFans.CN 收音机爱 好者资料库 SECTION 1. GENERAL SERVICING PRECAUTIONS NOTES REGARDING HANDLING OF THE PICK-UP 1. Notes for transport and storage 1) The pick-up should always be le

4、ft in its conductive bag until immediately prior to use. 2) The pick-up should never be subjected to external pressure or impact. 2. Repair notes 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

5、 and carefully, taking care to avoid external pressure and impact. If it is subjected to strong pressure or impact, the result may be an operational 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 f

6、or that reason the adjustment point and installation screws should absolutely never be touched. 4) Laser beams may damage the eyes! Absolutely 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

7、 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). The 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 attem

8、pt to disassemble the pick-up. Spring by excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do not 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

9、get inside the pick-up. - 1-2 - Storage in conductive bagDrop impact NEVER look directly at the laser beam, and dont let contact fingers or other exposed skin. Magnet How to hold the pick-up Pressure Pressure Cotton swab Conductive Sheet RadioFans.CN 收音机爱 好者资料库 NOTES REGARDING COMPACT DISC PLAYER RE

10、PAIRS 1. Preparations 1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode). These components 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

11、 be handled with care. 2) The pick-up is composed of many optical components and other high-precision components. Care must be taken, therefore, to avoid repair or storage where the temperature of humidity is high, where strong magnetism is present, or where there is excessive dust. 2. Notes for rep

12、air 1) Before replacing a component part, first disconnect the power supply lead wire from the unit 2) All equipment, measuring 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

13、 not place the pick-up on the bag. (This is because there is the possibility of damage by static electricity.) 4) To prevent 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 t

14、o come in contact with clothing, in order to prevent static electricity changes in the clothing to escape from the armband. 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(bu

15、tton malfunction, display, etc.). Using a pointed good conductor(such as driver), simply short the RESET jump wire on the 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

16、 the volume rotary knob and release it. 2. If you wish to operate the RESET jump wire, it is necessary to unplug the power cord. - 1-3 - Armband Conductive Sheet Resistor (1 Mohm) Resistor (1 Mohm) VOLUME KNOB UP DOWN VOLUME RESET jump wire ESD PRECAUTIONS Electrostatically Sensitive Devices (ESD) S

17、ome 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 followi

18、ng 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,

19、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

20、 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 suffici

21、ent 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 pa

22、ckaged 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 de

23、vice 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 liftin

24、g 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”

25、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. - 1-4 - - 1-5 - SPECIFICATIONS SECTION MODELFFH-286A/AD G

26、eneralPower supplyRefer to the back panel of the unit Power consumption30W Mass5.70kg Extemal dimensions(W X H X D)273X 330 X 360mm CDFrequency Response40-18000Hz Signal-to-noise ratio70dB Dynamic range70dB Tuning Range87.5-108.0MHz or 65-74MHz, 87.5-108.0MHz Intermediate Frequency10.7 MHz FMSignal-

27、to-noise ratio61/58dB Frequency Response60-10000Hz Tuning Range522-1611kHz or 530-1610kHz AMIntermediate Frequency450kHz Signal-to-noise ratio35 dB Frequency Response100-2000 Hz AMPOutput Power5W + 5W T.H.D0.3% Frequency Response42-20000Hz Signal-to-noise ratio80dB TAPETape Speed4.75cm/sec Wow Flutt

28、er0.25% (MTT-111,JIS-WTD) F.F/REW Time120sec(C-60) Frequency Response250-8000Hz Signal-to-noise ratio43dB Channel Separation50dB(P/B)/45dB(R/P) Erase Ratio55dB (MTT-5511) SpeakerMODELFE-286E Type1 Way 1 Speaker Impedance4 Frequency Response80-20000Hz Sound Pressure Level86dB/W(1m) Rated Input Power5

29、W Max.Input Power10W Net Dimension(W XH XD)180 X326 X 165.8mm Net Weight1.67kg NOTE : Specification are subject to change without notice in the course of product improvement. TUNER - 1-6 - MEMO - 2-1 - TAPE DECK ADJUSTMENT 1. AZIMUTH ADJUSTMENT Figure 1. Azimuth Adjustment Connection Diagram CH1 CH2

30、 Speaker Out Playback Mode Head Test Tape MTT-114 L ch R ch GND Dual-trace synchroscope Electronic Voltmeter L out R out Unit SECTION 2. ELECTRICAL ADJUSTMENTS This set has been aligned at the factory and normally will not require further adjustment. As a result, it is not recommended that any attem

31、pt is made to modificate any circuit. If any parts are replaced or if anyone tampers with the adjustment, realignment may be necessary. IMPORTANT 1. Check Power-source voltage. 2. Set the function switch to band being aligned. 3. Turn volume control to minimum unless otherwise noted. 4. Connect low

32、side of signal source and output indicator to chassis ground unless otherwise specified. 5. Keep the signal input as low as possible to avoid AGC and AC action. Deck ModeTest TapeTest PointAdjustmentAdjust for A Deck PlaybackMTT-114Speaker Out DECK Screw Maximum Azimuth Screw B Deck PlaybackMTT-114S

33、peaker OutAzimuth ScrewMaximum 2. MOTOR SPEED ADJUSTMENT Figure 2. Motor Speed Adjustment Connection Diagram Head Playback Mode Unit Speaker Out GND L out R out Record/Playback head Test Tape MTT-111 Frequency Counter Deck ModeTest TapeTest PointAdjustmentAdjust forRemark Normal SpeedMTT-111Speaker

34、OutVR2013kHz 1%A Deck HI-SpeedMTT-111Speaker Outmore than 5.4kHzHI-Speed Dubbing Mode - 2-2 - 3. RECORD BIAS ADJUSTMENT Head Unit PN202 GNDRecord/Playback head Test Tape MTT-5511 Record/Playback and Pause Mode Frequency Counter Deck ModeTest TapeTest PointAdjustmentAdjust for Rec/PauseMTT-5511 ERASE

35、 HEAD L203 60kHz5kHz (Auto stop) WIRE(PN202)85kHz5kHz(Auto Reverse) Figure 3. Record Bias Adjustment Connection Diagram 4. TUNER ADJUSTMENT Figure 4. Tuner(S curve) Adjustment Connection Diagram Unit Signal Generator GND Electronic OSCILLOSCOPE FM Antenna TerminalSpeaker ItemTest PointAdjustmentAdju

36、st for DC VoltageChecker IC Pin 26, 28L1060V50mV (FM) - 2-3 - TROUBLESHOOTING Turn power on. Is power on? Does initial read work? Does it play? Does it output audio? Check power supply circuit. PN807 PIN5, 6.2V PN807 PIN7, 5V IC803 PIN 2, 3.3V Check the connector PN801, PN802, PN809 Check the tracki

37、ng servo circuit. Check the PN807 PIN1, 3 OK YES YES YES YES YES YES NO NONO Check the DISK turns Check the Laser Check the focus circuit Check the TRAKING circuit NO NO - 2-4 - Fails to initial read A B 2V 5V 0V 5V 0V 1V 0V 1.2V 0V 0.8V NONO NO NO NO NO NO NO NO NO YES YES YES YES YES YES YES YES Y

38、ES YES YES YES Disc motor turns Does RF waveform appear? IC801 Pin3 Check the Data transmission from PN809 pin11 to CD DSP Check the Data transmission from PN809 pin13 to MICOM Check the change of SLDO Voltage(IC801 pin23) Check the change of SL +, SL - Voltage (IC802 pin 18, 19) Check the Voltage c

39、hange of PN 809 PIN20(OPEN, CLOSE) Defective connector PN809 Defective connector PN809, Defective MICOM Defective connector PN809, Defective IC801 Defective IC801 Defective IC802 Defective contact PN802 Defective PICK-UP Does laser light? focus coil drive wareform. TRACKING ERROR wareform Is rotatio

40、n normal? Defective IC801 Defective PICK-UP Is there no dropout of RF signal? Does FA+ waveform appear at IC802 pin13? Does TE waveform appear at 801 pin 15? - 2-5 - NO NO NO NO NO NO Laser does not light. Is “3.5V” applied to pin of IC 801? Is power supplied to laser Q801? (Q 801 collector: about 1

41、.8V) Does laser current flow? 1.0V across R808 Is data transferred from MICOM IC ? Does voltage appear at IC 802 pin 17, 18? Defective MICOM. Defective MICOM. Defective connector. Defective IC 801, 802 Defective slide motor and/or connector. Defective LMT SW and/or connector. Defective Q 801 and/or

42、laser. Defective laser and/or connector. Did pickup return to innermost circular? Does it stop at inner pick circular after shift? Is defect output from LM SW applied to pin 2 of PN802? R8081.0V R8081.0V YES YES YES YES OPENCLOSE YES YES YES YES YES YES 70 - 2-6 - B NO NO NO NO NO YES YES YES YES La

43、ser lights Does lens move up/down? Check the signal of FOCUS SEARCH (IC801 Pin 21) Chekc the signal of PN802 pin 13, 14 Does FE signal appear? (IC801 pin 13) Does DRF signal appear? (IC 801 pin67) Defective IC801 Defective IC802 Open activator and/or connector Defective IC801 Degraded laser diode Defective PICK-UP - 2-7 - (CH1) (CH2) 1. HF signal (RF signal ) waveform (IC801 pin 3) duri