NAD-T748-avr-sm 电路图 维修手册.pdf

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1、LAUNAMECIVRES AV Surround Sound Receiver T748 AV Surround Sound Receiver T748 RadioFans.CN 收音机爱 好者资料库 PRODUCT SAFETY SERVICING GUIDELINES1-3 * General Servicing Precautions * Insulation checking prodedure * Electrostatically Sensitive Devices W SECTION 1 SUMMARY CONTENTS SERVICING PRECAUTIONS1-4 SPE

2、CIFICATIONS1-5 DISASSEMBLY1-6 PRINCIPAL PART LOCATION1-7 EXPLODED VIE1-8 . . . . . . 1-2 RadioFans.CN 收音机爱 好者资料库 PRODUCT SAFETY SERVICING GUIDELINES CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY. NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFACTURERS APPROVAL. UNAUTHORIZED MODIFIC

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

4、 POTENTIAL HAZARDS AND INJURY 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 RESISTOR, PARALLELED BY

5、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 MEASUREMENTS FOR EACH EXP

6、OSED 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. NEVER INSTALL ANY PRODUCT

7、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, ETC. 3. AVOID PLACEME

8、NT 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 INSTRUCTIONS A PRODUCT MOUN

9、TED 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 CUSTOMERS AGAINST THE

10、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 THRESHOLDS OR DEEP PILE CARPETS.

11、 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 AGAINST THE USE OF EXTENSI

12、ON 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 “DANGEROUS VOLTAGE” WITHIN THE

13、PRODUCTS 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 ACCOMPANYING THE APPLIAN

14、CE. 1-3 RadioFans.CN 收音机爱 好者资料库 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 servicing precautions and a

15、ny 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 board, module, or any othe

16、r 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 capacitors may result in an e

17、xplosion hazard. 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, cottontipped swab, or comparable s

18、oft 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 Receiver and/or any of its el

19、ectrical 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 Checking Procedure Disconn

20、ect 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 than 1M-ohm. Note 1 : Acces

21、sible 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 Sensitive (ES) Devices. Examples o

22、f 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 semiconductor component or semic

23、onductor-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.

24、 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 exposure of the assembly. 3. Use only a grounded-tip soldering iron to solder or unsolder ES devices. 4. Use only an antistati

25、c 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 remove a replacement ES device

26、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 protective material from the

27、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. Minimize bodily motions when handing unpackaged re

28、placement 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.) 1-4 Amplifier SectionFM Tuner Section (Without notes 100.1MHz, 60dB) Output Power

29、(Front): egnaR gn i nuT:no i taR C.T.F t s zHK05:C zHM0.801 - zHM5.78 ,mumi n im l ennahc rep SMR st taw 08eps pet s zHK001:HA mor f smho 8 otn i nev i rd s l ennahc htobs 20Hz to 20KHz with no more than 0.08% Bd 54 : C : o i taR no i sserppuS MAno i t rot s id c i nomrah latot AH : 45 dB Surround O

30、utput Power (0.08% THD, 1KHz, 8 ohms): : )zHK1(no i t rot s iD c i nomraH latoT) tnorF( t taW 54 + 54 %8.0 : onoM) retneC( t taW 54 %0.1 : oeretS) r ruS( t taW 54 + 54 45 + 45 Watt (Back Surr) Freqency Response : 50Hz - 13KHz, +3/-3dB Total Harmonic Distortion (Front): Bd03 : C : )zHK1(no i tarapeS

31、oeretS)zHK1 , st taW 54 ta( %80.0 Bd03 : HA Audio input Sensitivity/Impedance : :o i taR es ioN-ot- lang iSsmhoK 74/Vm 052 : en i L * Mono : 60dB Output Level / Impedance * REC : 250 mV/2.2KohmsAM Tuner Section :egnaR gn i nuT : esnopseR ycneqerF )spet s zHK9(zHK0261-zHK225:CBd3- /3+ , zHK001 - zH02

32、 : en i L * AH:520KHz-1710KHz(10KHz steps) Signal-to-Noise Radio : 1 Watt Bd55 : yt i v i t i sneS e lbasU)A-FHI ( Bd 58 : en i L * Total Harmonic Distortion : 1.0% Bd53 : o i taR es ioN-ot- lang iSlor tnoC enoT BASS : +/- dB at 100Hz TREBLE : +/- dB at 10KHzGeneral Power Requirements : Digital audi

33、o Section C : AC230V, 50Hz zH06 ,V021CA : HA: ycneqerF gn i e lpmaS 32KHz, 44.1KHz, 48KHz, 96KHz, 192KHzPower Consumption : C : 2.0A AH : 4.5A latoT ,1 x deht iwsnu : ste l tuO CAecnadepmI / l eveL tupnI lat ig iD100W max.(1A) 3 x 761 x 534 : )D x H x W(sno i snemiDsmho 57/p-pV 5.0 : la i xaoC97 gK5

34、.11 : ) ten( thg i eWmBd12- mBd51- : lac i tpO Video Section Input Level/Impedance : 1.0Vp-p/75ohms Output Level/Impedance : 1.0Vp-p/75ohms *Linemeans Source 14, Front, MP * Improvements may result in specifications and features changing without notice * Illustrations may differ slightly from produc

35、tion models. 1-5 SPECIFICATIONS Factory Reset The select AM mode, then press/hold “listening mode” button. DISASSEMBLY REMOVAL OF FRONT PANEL 1-6 PRINCIPAL PART LOCATION 1-7 1-8 T748AH EXPLODED VIEW PARTS LIST 10CABINET,TOPCKC1A188B22 FRONT PCB ASSY 23 27 24 25 26 17 18 19 20 22 21 11 12 13 14 16 15

36、 PANEL,REAR BRACKET RUBBER,FOOT FOOT COP12370B CHG1A297 CKL1A086 CKF2A445ZK1 CMD1A674 BRACKET 8 9 5 4 3 7 6 FUNCTION KNOB ASSY COVER,JACK PANEL,AL POWER KNOB ASSY NO 2 1 VOLUME KNOB ASSY DESCRIPTION CKM1A208XC64 CBT1A1103ZA CGK2A126ZA CMD2A563 CGR1A476B29 CGK1A145ZA PARTS NO 1 1 1 1 4 4 1 1 1 2 1 1

37、1 1 Q,ty 1 27-1COP12370-1 28MAIN PCB ASSYCOP12372B1 1 1 1 1 INPUT PCB ASSY29COP12371C1 WINDOW ,FIPCGU1A434Z1 1 1 CGW2A475RBB29PANEL,FRONT1 REMARK 1 KNOB,SOURCECBT1A1104B292 1 CHASSIS ,BOTTOMCUA1A3271 SUPPORT,PCB 31CRE1A0731 HEAT SINKCMY1A369 BRACKET,PCBCMD1A7342 BRACKET , FANCMD1A694 KNOB,VOLUMECBN1

38、A216 CAP,VOLUMECGK1A145C64 KNOB,POWERCBT1A1103B291 INDICATOR,POWERCGL1A280Z1 CAP,FUNCTIONCGK1A126C64 KNOB,FUNCTIONCBT1A1102B29 HDMI PCB ASSY1COP12374C S1 S5 S4 S3 NO 54CTB3+8JFZRSCREW SCREW SCREWCTB4+6FFZR CHD1A012R CTW3+12JR 14 4 6 DESCRIPTIONPARTS NO.Q,ty SCREWCTWS3+10GR2 S6 CHD3A012R8S7 SCREW,SPE

39、CIALCHD1A036R4S8 SCREW,TRANSCHD1A023R4 S9 S10 S1113CTB3+6FFZRSCREW 1 FAN,MOTOT(60*60*25)1 FAN,MOTOR(80*80*25)1CFNRDH8025S CFNRDM6025S CWZPM5003TW91A2P WIRE ASSY 1 1 1 1 1 1 1 1 1 1 1 COP12370-2 COP12370-3 COP12370-4 COP12370-5 COP12370-6 COP12370-7 HOLDER , PCBCHE1704 BRACKET , FANCMD1A5061 TRANS,PO

40、WER1 1 SCREW,SPECIALCHD1A036FZR2 SCREW,SPECIAL SCREW,SPECIAL S121CTW3+8JRSCREW 28-1 28-2 1COP12370-8 COP12372-1 COP12372-2 SUB PCB ASSY31COP12373C1 31-1 31-2 31-3 COP12373-1 1 1 1 31-41 COP12373-2 COP12373-3 COP12373-4 30 1 1 29-1 29-2 COP12371-1 COP12371-2 1 1 CLT5V061ZU 27-2 27-3 27-4 27-5 27-6 27

41、-7 27-8 1-9 1-10 S1 S1 S1 S1 S1 S3 S1 S1 S5 S3 S1 S3 S1 S1 S4 S4 S1 S10 S11 S11 S11 S11 S1 S11 S8 S12 S1 S6 S1 S7 S11 S1 S1 S1 X5 S5 S1 S1 S1 S9 S12 S1 S1 3 1 2 5 4 6 7 8 6 9 18 19 27-1 27-5 27-2 27-4 27-3 9 16 17 10 25 13 12 11 15 20 21 23 24 22 14 27-7 27-8 27-6 28-1 28-2 29-1 30 31-1 31-2 31-3 31

42、-4 29-2 T748AH EXPLODED VIEW 1-11 T748C EXPLODED VIEW PARTS LIST 10CABINET,TOPCKC1A188B22/G39 FRONT PCB ASSY 23 27 24 25 26 17 18 19 20 22 21 11 12 13 14 16 15 PANEL,REAR BRACKET RUBBER,FOOT FOOT COP12370B CHG1A297 CKL1A086 CKF1A445ZK1 CMD1A674 BRACKET 8 9 5 4 3 7 6 FUNCTION KNOB ASSY COVER,JACK PAN

43、EL,AL POWER KNOB ASSY NO 2 1 VOLUME KNOB ASSY DESCRIPTION CKM1A208XC64 CBT1A1103ZA CGK2A126ZA CMD2A563 CGR1A476B29 CGK1A145ZA PARTS NO 1 1 1 1 4 4 1 1 1 2 1 1 1 1 Q,ty 1 27-1COP12370-1 28MAIN PCB ASSYCOP12372B1 1 1 1 1 INPUT PCB ASSY29COP12371B1 WINDOW ,FIPCGU1A434Z1 1 1 CGW2A475RBB29PANEL,FRONT1 RE

44、MARK 1 1 KNOB,SOURCECBT1A1104B292 1 CHASSIS ,BOTTOMCUA1A3271 SUPPORT,PCB 31CRE1A0731 HEAT SINKCMY1A369 BRACKET,PCBCMD1A7342 BRACKET , FANCMD1A694 KNOB,VOLUMECBN1A216 CAP,VOLUMECGK1A145C64 KNOB,POWERCBT1A1103B291 INDICATOR,POWERCGL1A280Z1 CAP,FUNCTIONCGK1A126C64 KNOB,FUNCTIONCBT1A1102B29 HDMI PCB ASS

45、Y1COP12374B S1 S5 S4 S2 S3 NO 54CTB3+8JFZRSCREW SCREW SCREWCTB4+6FFZR CHD1A012R CTW3+12JR 14 4 6 DESCRIPTIONPARTS NO.Q,ty SCREWCTWS3+10GR2 S6 CHD3A012R8S7 SCREW,SPECIALCHD1A036R4S8 SCREW,TRANSCHD1A023R4 S9 S10 S1113CTB3+6FFZRSCREW 1 FAN,MOTOT(60*60*25)1 FAN,MOTOR(80*80*25)1CFNRDH8025S CFNRDM6025S CW

46、ZPM5003TW91A2P WIRE ASSY 1 1 1 1 1 1 1 1 1 1 1 HOLDER , PCBCHE1704 BRACKET , FANCMD1A5061 TRANS,POWER1 1 CTB3+8JFC SCREW,SPECIALCHD1A036FZR2 SCREW,SPECIAL SCREW,SPECIAL 10 S121CTW3+8JRSCREW 28-1 28-2 1 COP12372-1 COP12372-2 SUB PCB ASSY31COP12373B1 31-1 31-2 31-3 COP12373-1 1 1 1 31-41 COP12373-2 CO

47、P12373-3 COP12373-4 30 1 1 27-2 27-3 27-4 27-5 27-6 27-7 27-8 COP12370-2 COP12370-3 COP12370-4 COP12370-5 COP12370-6 COP12370-7 COP12370-8 29-1COP12371-11 29-2COP12371-21 CLT5V061ZE SCREW 1-121-13 S1 S1 S1 S1 S1 S3 S1 S1 S5 S3 S1 S3 S1 S1 S4 S4 S1 S10 S11 S11 S11 S11 S1 S11 S8 S12 S1 S6 S1 S7 S11 S1 S1 S1 S2 S2 X5 S5 S1 S1 S1 S9 S12 S1 S1 3 1 2 5 4 6 7 8 6 9 18 19 27-1 27-5 27-2 27-4 27-3 9 16 17 10 25 13 12 11 15 20 21 23 24 22