NAD-T747-avr-sm 电路图 维修手册.pdf

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1、L A U N A M E C I V R E S AV Surround Sound Receiver T747 AV Surround Sound Receiver T747 RadioFans.CN 收音机爱 好者资料库 1-2 SECTION 1 SUMMARY CONTENTS PRODUCT SAFETY SERVICING GUIDELINES. 1-3 SERVICING PRECAUTIONS . 1-4 * General Servicing Precautions * Insulation checking prodedure * Electrostatically Se

2、nsitive Devices SPECIFICATIONS . 1-5 DISASSEMBLY . 1-6 PRINCIPAL PART LOCATION. 1-7 . 1-8EXPLODED VIEW . RadioFans.CN 收音机爱 好者资料库 1-3 PRODUCT SAFETY SERVICING GUIDELINES CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY. NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFACTURER S APPROVAL.

3、 UNAUTHORIZED MODIFICATIONS WILL NOT ONLY VOID THE WARRANTY, BUT MAY LEAD TO YOUR BEING LIABLE FOR ANY RESULTING PROPERTY DAMAGE OR USER INJ URY. SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING SAFETY CHECKS AND SERVICING GUIDELINES. TO DO OTHERWISE,

4、 INCREASES THE RISK OF POTENTIAL HAZARDS AND INJ URY TO THE USER. WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR PROTECTION FROM AC LINE SHOCK. SAFETY CHECKS AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRECTED. A CHECK SHOULD BE MADE OF THE FOLLOWING. SUBJECT : FIRE CONNECT A 1500 OHM 10 WATT R

5、ESISTOR, PARALLELED BY A .15 MFD, 150V AC TYPE CAPACITOR BETWEEN A KNOWN GOOD EARTH GROUND (WATER PIPE, CONDUIT, ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME. MEASURE THE AC VOLTAGE ACROSS THE COMBINATION OF 1500 OHM RESISTOR AND .15 MFD CAPACITOR. REVERSE THE AC PLUG AND REPEAT AC VOLTAGE ME

6、ASUREMENTS FOR EACH EXPOSED METALLIC PART. VOLTAGE MEASURE MUST NOT EXCEED 75 VOLTS R.M.S. THIS CORRESPONDS TO 0.5 MILLIAMP AC ANY VALUE EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL SHOCK HAZARD AND MUST BE CORRECTED IMMEDIATELY. SUBJECT : GRAPHIC SYMBOLS SUBJECT : TIPS ON PROPER INSTALLATION 1. NEV

7、ER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS, CUBBYHOLE OR CLOSELY FITTING SHELF SPACE. OVER OR CLOSE TO HEAT DUCT, OR IN THE PATH OF HEATED AIR FLOW. 2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIO INSTALLATIONS WHERE DEW IS A FACTOR, NEAR STEAM RADIATORS WHERE STEAM LEAKAGE IS A FACTOR

8、, ETC. 3. AVOID PLACEMENT WHERE DRAPERIES MAY OBSTRUCT REAR VENTING. THE CUSTOMER SHOULD ALSO AVOID THE USE OF DECORATIVE SCARVES OR OTHER COVERINGS WHICH MIGHT OBSTRUCT VENTILATION. 4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMERCAL MOUNTING KIT MUST FOLLOW THE FACTORY APPROVED MOUNTING INST

9、RUCTIONS A PRODUCT MOUNTED TO A SHELF OR PLATFORM MUST RETAIN ITS ORIGINAL FEET (OR THE EQUIVALENT THICKNESS IN SPACERS) TO PROVIDE ADEQUATE AIR FLOW ACROSS THE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERS MUST NOT TOUCH ANY PARTS OR WIRING. PERFORM LEAKAGE TEST ON CUSTOMIZED INSTALLATIONS. 5. CAUTION

10、 CUSTOMERS AGAINST THE MOUNTING OF A PRODUCT ON SLOPING SHELF OR A TILTED POSITION, UNLESS THE PRODUCT IS PROPERLY SECURED. 6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE ON ITS MOUNTING TO THE CART. CAUTION THE CUSTOMER ON THE HAZARDS OF TRYING TO ROLL A CART WITH SMALL CASTERS ACROSS THRESHOLD

11、S OR DEEP PILE CARPETS. 7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR STAND WHICH HAS NOT BEEN LISTED BY UNDERWRITERS LABORATORIES, INC. FOR USE WITH THEIR SPECIFIC MODEL OF TELEVISION RECEIVER OR GENERICALLY APPROVED FOR USE WITH T.V. S OF THE SAME OR LARGER SCREEN SIZE. 8. CAUTION CUSTOMERS AG

12、AINST THE USE OF EXTENSION CORDS, EXPLAIN THAT A FOREST OF EXTENSIONS SPROUTING FROM A SINGLE OUTLET CAN LEAD TO DISASTROUS CONSEQUENCES TO HOME AND FAMILY. THE LIGHTNING FLASH WITH ARROWHEAD SYMBOL, WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE USER TO THE PRESENCE OF UNINSULATED “DANGER

13、OUS VOLTAGE” WITHIN THE PRODUCT S ENCLOSURE 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 USER TO THE PRESENCE OF IMPORTANT OPERATING AND MAINTENANCE (SERVICING) INSTRUCTIONS IN THE LITERATURE

14、 ACCOMPANYING THE APPLIANCE. RadioFans.CN 收音机爱 好者资料库 1-4 SERVICING PRECAUTIONS CAUTION : Before servicing the A/V Receiver covered by this service data and its supplements and addends, read and follow the SAFETY PRECAUTIONS. NOTE : if unforeseen circumstances create conflict between the following se

15、rvicing precautions and any of the safety precautions in this publication, always follow the safety precautions. Remember Safety First: General Servicing Precautions 1. Always unplug the A/V Receiver AC power cord from the AC power source before: (1) Removing or reinstalling any component, circuit b

16、oard, module, or any other assembly. (2) Disconnecting or reconnecting any internal electrical plug or other electrical connection. (3) Connecting a test substitute in parallel with an electrolytic capacitor. Caution : A wrong part substitution or incorrect polarity installation of electrolytic capa

17、citors may result in an ex plosion haz ard. 2. Do not spray chemicals on or near this A/V Receiver or any of its assemblies. 3. Unless specified otherwise in this service data, clean electrical contacts by applying an appropriate contact cleaning solution to the contacts with a pipe cleaner, cottont

18、ipped swab, or comparable soft applicator. Unless specified otherwise in this service data, lubrication of contacts is not required. 4. Do not defeat any plug/socket B+ voltage interlocks with which instruments covered by this service manual might be equipped. 5. Do not apply AC power to this A/V Re

19、ceiver and/or any of its electrical assemblies unless all solid-state device heat sinks are correctly installed. 6. Always connect test instrument ground lead to the appropriate ground before connecting the test instrument positive lead. Always remove the test instrument ground lead last. Insulation

20、 Checking Procedure Disconnect the attachment plug from the AC outlet and turn the power on. Connect an insulation resistance meter(500V) to the blades of the attachment plug. The insulation resistance between each blade of the attachment plug and accessible conductive parts (Note 1) should be more

21、than 1M-ohm. Note 1 : Accessible Conductive Parts including Metal panels, Input terminals, Earphone jacks, etc. Electrostatically Sensitive (ES) Devices Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensiti

22、ve (ES) Devices. Ex amples of typical Es 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 semi

23、conductor 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 powe

24、r to the unit under test. 2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or ex posure of the assembly. 3. Use only a grounded-tip soldering iron to solder or unsolder ES devi

25、ces. 4. Use only an antistatic solder removal device. Some solder removal devices not classified a “anti-static” can generate electrical charges sufficient to damage ES devices. 5. Do not use freonpropelled chemicals. These can generate electrical charge sufficient to damage ES devices. 6. Do not re

26、move a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil, or comparable conductive material). 7. lmmediately before removing the

27、protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed. Caution : Be sure no power is applied to the chassis or circuit, and observe all other safety precautions. 8. Minimiz e bodily moti

28、ons when handing unpackaged replacement ES devices. (Normally 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 ES device.) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

29、 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? SPECIFICATIONS 1-5 1-6 DISASSEMBLY 1 REMOVAL OF TOP COVER 2 REMOVAL OF FRONT PANEL 1-7 PRINCIPAL PARTS LOCATION T747AH EXPLODED VIEW PARTS LIST (Graphite) 1-8 NOTE * AMP ASSEMBLY #31 UDQS correspond to the data on DQ8-DQ15 SYMBOLTYPEDESCRIPTION DM (x8) Inpu

30、t Input Data Mask: DM is an input mask signal for write data. Input data is masked when DM is sampled HIGH along with that input data during a WRITE access. DM is sampled on both edges of DQS. Although DM pins are input only, the DM loading matches the DQ and DQS loading. For the x16, LDM correspond

31、s to the data on DQ0-DQ7; UDM corresponds to the data on DQ8-DQ15. Input / Output VrefInputSSTL_ 2 reference voltage. UDQS, LDQS (x16) UDM, LDM (x16) 2-9 BLOCK DIAGRAM /CS/RAS /CAS/WEDM Memory Array Bank # 0 DQ0 - 7 I/O Buffer Memory Array Bank # 1 Memory Array Bank # 2 Memory Array Bank # 3 Mode Re

32、gister Control Circuitry Address Buffer A0-12 BA0,1 Clock Buffer CLKCKE Control Signal Buffer DQS Buffer DQS DLL /CLK A3 S56D3 0ETP BLOCK DIAGRAM 2-10 BLOCK DIAGRAM ( IC152: ES29LV320FT70TG) 2-11 BLOCK DIAGRAM ( IC151:FLI30336AC) 2-12 2-13 BLOCK DIAGRAM ( IC134:NJM2285) IC113: NJM2566V: VIDEO AMP) 2

33、-14 13 12 11 REF 1 2 3 4 7 5 6 14 8 10 9 V+ 1 VEE1 VEE2 VEE3 GND VIN1 VIN2 VIN3 VOUT1 VOUT2 VOUT3 PowerSave BIAS 6dB AMP 75 Driver BIAS 75 Driver 6dB AMP BIAS 75 Driver 6dB AMP V+ 2 V+ 3 BLOCK DIAGRAM ( IC133:NJM2581) 9 10 8 5 6 7 4 3 2 1 11 1213 16 15 14 17 18 19 20 21 22 23 24CH1 IN1 CH1 IN3 CH1 I

34、N2 SW1 SW2 GND CH1 OUT V-1 CH2 OUT CH3 IN2 CH3 IN3 V+2 CH2 IN3 CH2 IN1 CH3 OUT CH3 IN1 GND CH2 IN2 GND PS 75? Driver Bias Con t 2 Con t 1 Con t 1 Con t 2 Con t 1 Con t 2 6dB Amp Bias Bias Bias Bias Bias Bias Bias 75? Driver 75? Driver Bias 6dB Amp 6dB Amp GNDGND V+1 V-2 9 10 8 5 6 7 4 3 2 1 1112 13

35、16 15 14 17 18 19 20 21 22CH1 IN1 CH1 IN3 CH1 IN2 SW1 SW2 GND CH1 OUT V-1 CH2 OUT CH3 IN2 CH3 IN3 V+2 CH2 IN3 CH2 IN1 CH3 OUT CH3 IN1 V+1 CH2 IN2 V-2 PS 75? Driver Bias Con t 2 Con t 1 Con t 1 Con t 2 Con t 1 Con t 2 6dB Amp Bias Bias Bias Bias Bias Bias Bias 75? Driver 75? Driver Bias 6dB Amp 6dB A

36、mp GNDGND BLOCK DIAGRAM ( IC135:NJM2586A) DMP24SDIP22 2-15 IC131:NJW1321FP: VIDEO SW) 2-16 2-17 SYSTEM BLOCK DIAGRAM Lout REC Lch Rout Input ATT Out L for ADC REC AGND Volume Out R for ADC Rch AVCC Multi Rin Multi Lin 3 4 5 6 7 8 9 1 2 Tone Rch Tone Bass?(+?/? ?86?4?7?/?(?,? ?&?#?/? ?&?(?0?(? ?#?.?

37、? #?!? ?$?%?8?#?!?6? ? #?!? ?$?%?8?9?8?#?!?!? ? ? 2 -89 3-1 SECTION 3 ELECTRICAL PARTS LIST ? RESISTORS AND CAPACITORS Notes : * Please use this part number for parts order. * IMPORTANT SAFETY NOTICE. Components identified by! mark have special characteristics important for safety. When replacing an

38、y of these components, use only manufacture s specified parts. * The unit of resistance is ohm(?) k=1000? , M=1000? * The unit of capacitance is microfarad(?) p=10-6 ? ? Number ing System of Resistor example CRD 25 F J 101 Type Wattage Shape Tolerance Value WATTAGE K(C)RDCARBON10 : 1/10 WF : 1 % K(C

39、)RJCARBON CHIP14 : 1/4 WJ : 10 % K(C)RGMETAL OXIDE20 : 1/5 WK : 20 % K(C)RFMETAL CEMENT25 : 1/4 W K(C)RQFUSIBLE1 : 1 W 2 : 2 W 3 : 3 W ? Number ing System of Capacitor example CCC T 1H 101 K B Type Voltage Value Tolerance Peculiarity HCEA TypeOther HCB CERAMIC0J : 6.3V1H : 50V DCC : 0.25? CCC CERAMIC1A : 10V1 : 125V DCG : 2 % CCK CERAMIC1C : 16VKC : 400V ACJ: 5 % HCQ MYLAR1E : 25VK : 10 % HCU CERAMIC CHIP1H : 50VZ : +80%,-20% HCE ELECT.1V : 35V Toler ance TOLERANCERESISTOR TYPE Capacitor Type VOLTAGE ? ? ? ? ? ? ?