Akai-AMI721-cs-sm 电路图 维修手册.pdf

AKAI ELECTRONICS CO., LTD. Service Manual MINI COMPONENT SYSTEM Model : AMI-721L/R RadioFans.CN 收音机爱 好者资料库 1 TABLE OF CONTENTS SAFETY PRECAUTIONS . 2 SAFETY INSTRUCTION. 4 SPECIFICATION . 6 DISASSEMBLY . 7 REMOVE OF THE TOP COVER AND SIDE COVER .7 REMOVE OF THE CD MECHANISM .7 REMOVE THE PANEL FRONT ASSEMBLY .7 PRINCIPAL PARTS LOCATION . 8 DISASSEMBLY OF THE MAIN COMPONENTS . 9 EXPLODED VIEW AND PARTS LIST . 14 ADJUSTMENTS . 16 PARTS LIST . 18 RadioFans.CN 收音机爱 好者资料库 2 WARNING: TO PREVENT FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE. CAUTION :TO REDUCE THE RISK IF ELECTRIC SHOCK, DO NOT REMOVE COVER (OR BACK). NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL. THIS SYMBOL IS INTENDED TO ALERT THE USER TO THE PRESENCE OF UNINSULTED DANGEROUS VOLTAGE WITHIN THE PRODUCTS ENCLOSURE THAT MAY BE SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK TO PERSONS. THIS SYMBOL IS INTENDED TO ALERT THE USER TO THE PRESENCE OF IMPORTANT OPERATING AND MAINTENANCE (SERVICING) INSTRUCTIONS IN THE LITERATURE ACCOMPANYING THE APPLIANCE. CAUTION TO PREVENT ELECTRIC SHOCK, DO NOT USE THIS POLARIZED AC PLUG WITH AN EXTENSION CORD, RECEPTACLE OR OTHER OUTLET UNLESS THE BLADES CAN BE FULLY INSERTED TO PREVENT BLADE EXPOSURE. LASER SAFETY THIS UNIT EMPLOYS A LASER. ONLY QUALIFIED SERVICE PERSONNEL SHOULD REMOVE THE COVER OR ATTEMPT TO SERVICE THIS DEVICE DUE TO POSSIBLE EYE INJURY. CAUTION : USE OF ANY CONTROLS, ADJUSTMENTS, OR PROCEDURES OTHER THAN THOSE SPECIFIED HEREIN MAY RESULT IN HAZARDOUS RADIATION EXPOSURE. CAUTION : TO PREVENT ELECTRIC SHOCK, MATCH WIDE BLADE OF PLUG TO WIDE SLOT, FULLY INSERT. ATTENTION : POUR EVITER LES CHOCS ELECTRIQUES, INTRODUIRE LA LAME LA PLUS LARGE DE LA FICHE DANS LA BORNE CORRESPON- DANTE DE LA PRISE ET POUSSER JUSQUAU FOND. Important Safety Instructions - All the safety and operating instructions should be read before the appliance is operated. - The safety and operating instructions should be retained for future reference. - All warnings on the appliance and in the operating instructions should be adhered to. - All operating and use instructions should be followed. 1. Water and Moisture - The appliance should not be used near water - for example, near a bathtub, washbowl, kitchen sink, laundry tub, in a wet basement, or near a swimming pool, and the like. 2. Carts and Stands - The appliance should be used only with a cart or stand that is recommended by th manufacturer. 3. An appliance and cart combination should be moved with care. Quick stops, excessive force, and uneven surfaces may cause the appliance and cart combination to overturn. 4. Wall or Ceiling Mounting - The appli- ance should be mounted to a wall or ceiling only as recommended by the manufacturer. 5. Ventilation - The appliance should be situated so that its location or position does not interfere with its proper ventilation. For example, the appliance should not be situated on a bed, sofa, rug, or similar surface that may block the ventilation openings; or, placed in a built- in installation, such as a bookcase or cabinet that may impede the flow of air through the ventilation openings. 6. Heat - The appliance should be situated away from heat sources such as radiators, heat registers, stoves, or other appliances (including amplifiers) that produce heat. 7. Power Sources - The appliance should be connected to a power supply only of the type described in the operating instructions or as marked on the appliance. 8. Grounding or Polarization - The precautions that should be taken so that the grounding or polarization means of an appliance is not defeated. 9. Power - Cord Protection - Power- supply cords should be routed so that they are not likely to be walked on or pinched by items placed upon or against them, paying particular attention to cords at plugs, convenience receptacles, and the point where they exit from the appliance. 10.Protective Attachment Plug - The appliance is equipped with an attachment plug having overload protection. This is a safety feature. See Instruction Manual for replacement or resetting of protective device. If replacement of the plug is required, be sure the service technician has used a replacement plug specified by the manufacturer that has the same overload protection as the original plug. 11.Cleaning - The appliance should be cleaned only as recommended by the manufacturer. 12.Power Lines - An outdoor antenna should be located away from power lines. SAFETY PRECAUTIONS CAUTION RISK OF ELECTRIC SHOCKS DO NOT OPEN PORTABLE CART Figure 2 RadioFans.CN 收音机爱 好者资料库 3 SAFETY PRECAUTIONS 13.Outdoor Antenna Grounding - If an outside antenna is connected to the receiver be sure the antenna system is grounded so as to provide some protection against voltage surges and built- up static charges. Article 810 of the National Electrical Code, ANSI/NFPA 70, provides information with regard to proper grounding of the mast and supporting structure, grounding of the lead- in wire to an antenna- dis charge unit, size of grounding conductors,location of antenna- discharge unit, connection to grounding electrodes and requirements for the grounding electrode. See Figure 1. 14.Non- use Periods - The power cord of the appliance should be unplugged from the outlet when left unused for a long period of time. 15.Object and Liquid Entry - Care should be taken so that objects do not fall and liquids are not spilled into the enclosure through openings. 16.Damage Requiring Service - The appliance should be serviced by qualified service personnel when: a) The power- supply cord or the plug has been damaged; or b) Objects have fallen, or liquid has been spilled into the appliance; or c) The appliance has been exposed to rain; or d) The appliance does not appear to operate normally or exhibits a marked change in performance; or e) The appliance has been dropped, or the enclosure damaged. 17.Servicing - The user should not attempt to service the appliance beyond that described in the operating instructions. All other servicing should be referred to qualified service personnel. ANTENNA DISCHARGE UNIT (NEC SECTION 810- 20) ANTENNA LEAD IN WIRE POWER SERVICE GROUNDING ELECTRODE SYSTEM (NEC ART 250 PART H) GROUND CLAMP ELECTRIC SERVICE EQUIPMENT GROUNDING CONDUCTORS (NEC SECTION 810- 21) GROUND CLAMPS EXAMPLE OF ANTENNA GROUNDING NEC - NATIONAL ELECTRICAL CODE 4 SAFETY INSTRUCTION PRECAUTIONS DURING SERVICING 1. Parts identified by the (*) symbol parts are critical for safety. Replace them only with parts whose numbers are speci- fied. 2. In addition to safety, other parts and assemblies are specified for conformance with such regulations as those applying to spu- rious radiation. These must also be replaced only with specified replacements. Examples: RF converters, tuner units, antenna selection switches, RF cables, noise- blocking capacitors, noise- blocking filters, etc. 3. Use specified internal Wiring. Note especially: 1) Wires covered with PVC tubing 2) Double insulated wires 3) High voltage leads 4. Use specified insulating materials for hazardous live parts. Note especially: 1) Insulating Tape 2) PVC tubing 3) Spacers (insulating barriers) 4) Insulating sheets for transistors 5) Plastic screws for fixing micro switches 5. When replacing AC primary side components (transformers, power cords, noise blocking capacitor, etc.), wrap ends of wires securely about the terminals before soldering. 6. Make sure that wires do not contact heat generating parts (heat sinks, oxide metal film resistors, fusible resistors, etc.) 7. Check if replaced wires do not contact sharply edged or pointed parts. 8. Also check areas surrounding repaired parts. 9. Make sure that foreign objects (screws, solder droplets, etc.) do not remain inside the set. MAKE YOUR CONTRIBUTION TO PROTECT THE ENVIRONMENT Used batteries with the ISO symbol for recycling as well as small accumulators (rechargeable batter- ies), mini- batteries(cells) and starter batteries should not be thrown into the garbage can. Please leave them at an appropriate depot. SAFETY CHECK AFTER SERVICING After servicing, make measurements of leakage- current or resis- tance in order to check if exposed parts are acceptably insulated from the supply circuit. The leakage- current measurement should be done between accessible metal parts, (such as chassis, ground terminal, microphone jacks, signal input/ output connectors, etc.) and the earth ground through a resister of 1500 ohm paralleled with a 0.15 F capacitor, under the units nor- mal working condition. The leakage- current should be less the 0.5mA rms AC. The resistance measurement should be done between accessible exposed metal parts and power cord plug prongs with the power switch ON(if included). The resistance should be more than 2.2Mohms. PRECAUTIONS IN REPAIRING When repairing or adjusting the unit, please note the following points 1. Do not put excessive pressure on the vechanical part (operation part), including the pick- up block, as extremely high mechanical precision is required in these parts. 2. When the base is removed for repair or adjustment. Make sure that there are no metal objects between the P.C board or the mecha paarts and the base. 3. The Micro- computer and the CD signal processing ICsmay be damaged by static electricity or leakage from a soldering iron during repairing. While soldering, please take the precautions against leakage as in the illustration. 4. Do not loosen any screws in the pick- up block. Please refer to NOTE when replacing the pick upn block. 5. To avoid gazardous invisible Laser Radiation, do not look at the Laser Beam (Objective lens) directly. 6. On model for some countrise, laser warning labels are affixed on and inside of the unit as shown below. For your safety, read these labels carefully before repairing or adjusting the unit. CAUTION The use of controls or adjustments or the performance of procedures other than those specified herein may result in hazardous radiation. EUROPE, SCANDINAVIA, UK and AUSTRALIA CLASS 1 LASER PRODUCT KLASSE 1 LASER PRODUKT LUOKAN 1 LASER LAITE KLASS 1 LASER APPARA Label affixed on the rear panel of the unit CAUTION : INVISIBLE LASER RADIATION WHEN OPEN AND INTERLOCK DEFEATED AVOID EXPOSURE TO BEAM ADVARSEL: USYNLIG LASERSTRALING VED AB- NING SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION. UNDGAUDETTELSE FOR STALING. VARO: AVATTAESSA JA SUOJALUKITUS OHITET. TAESSA OLET ALTTIINA NAKYMATTOMALLA LASERSATE. LYLLE ALA KATSO SATEESEEN! VARNING: OSYNLIG LASERS TRALNING NAR DENNA DEL AR OPPNAD OCH SPARREN AR URKOPPLAD. BETRAKTA EJ STRALEN! * Label affixed on the CD MECHA BLOCK GND 5 INFORMATION SYMBOLS FOR PRIMARY DESTINATION Alphabet indicates the destination of the units as listed below. VOLTAGE CONVERSION ( U Y Model only) Before connecting the power cord, set the VOLTAGE SELEC- TOR located on the rear panel of the AC- 425K/625K so that the cor- rect voltage for your area is indicated. TEST MODE Various kind of test modes are installed in this units microcom- puter in order to test them on the production line. Following test modes among the various test modes can be used for adjust- ment, operation check or maintenance. To terminate the test mode, simply press the POWER ON/STANDBY button or discon- nect the AC power cord from the AC outlet. 1. DECK TEST MODE This test mode can be used for tape speed adjustment as well as bias oscillator frequency adjustment in TAPE DECK section. While pressing and holding the TAPE II and (F)buttons, connect the AC power cord to AC outlet. The function turns to TAPE I and DUBX1 as well as T P I indicators on the FLD light when this mode is engaged. 2. DECK CLEANING MODE This test mode can be used for cleaning of the TAPE DECK mech- anism. Because, this mode enables engaging of the playback, fast forward (FF), and rewind (RWD) modes without a cassette tape, it makes the cleaning (such as the capstan shaft, magnetic head, pinch roller etc.) easier. While pressing and holding the TAPE I and (F) button, connect the AC power cord to the AC outlet. The tape run indicator lightwithout the cassette tape when this mode is engaged. SymbolPrincipal Destination AUSA BUK EEurope(except,UK) SAustralia VGermany UUniversal Y*Custom version 6 SPECIFICATION 7 DISASSEMBLY 1. REMOVE OF THE TOP COVER AND SIDE COVER 1) Remove the 5 screws(a) on the TOP COVER. 2) Removee the 7 screw(b) on the SIDE and BACK COVER. 2. REMOVE OF THE CD MECHANISM 1) Open the DOOR CD by pressing OPEN/CLOSE button on the PANEL FRONT while the POWER is tuned on. 2) Remove the DOOR CD. 3) Disconnect of the cable and 2 connectors on the MAIN and CD PCB. 4) Remove the 4 screw. 3. REMOVE THE PANEL FRONT ASSEMBLY 1) Disconnect the wire on the MAIN PCB. 2) Remove the 2 screws(a) on the PANEL FRONT bottom side. 3) Releasing the middle side and bottom side stoppers. 4) Pull out the PANEL FRONT ASSEMBLY. 8 PRINCIPAL PARTS LOCATION 9 DISASSEMBLY OF THE MAIN COMPONENTS 1. CD PLAYER BLOCK The exchange of driving unit ass y. A. Separation of D/U ass y. 1. Short terminal (1) on pick- up PCB after separating mecha from set. 2. Take down D/U ass y (2) through turning relay gear (3) in CCW direction. 3. Release screw (5). 4. Push slider L (6) in the direction of screw (5). 5. Separate D/U ass y (2). B. Assembly of D/U ass y. 1. Put D/U ass y between slide R (7) and slider L (6). 2. Push slider L (6) in the opposite direction of screw (5). 3. Lock screw (5). 4. Open terminal (1) on pick- up PCB. 5. Put mecha on set. Power must be supplied before the exchange. During the exchange, prevention band for static electricity must be in wear. (To avoid the damage of pick- up for static electricity) NOTE DISASSEMBLY ASSEMBLY 10 DISASSEMBLY OF