NAD-M3-int-sm 维修电路原理图.pdf

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1、SERVICE MANUALSERVICE MANUALM3 C/AHMODEL : M3SERVICE MANUAL NAD 2005NAD ELECTRONICS INTERNATIONALTORONTOM3 C/AHINTEGRATE AMPLIFLERM3 C/AHINTEGRATE AMPLIFIERINTEGRATE AMPLIFIERRadioFans.CN 收音机爱 好者资料库CONTENTSSECTION 1 . . . .SUMMARYSECTION 2 . . . .CABINET & MAIN CHASSISSECTION 3 . . . .ELECTRICALSECT

2、ION 4 . . . .REPLACEMENT PARTS LISTRadioFans.CN 收音机爱 好者资料库SECTION 1SUMMARYCONTENTSPRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO PRODUCTS. 1-2SERVICING PRECAUTIONS . 1-3 General Servicing Precautions Insulation Checking Prodedure Electrostatically Sensitive DevicesSPECIFICATIONS. 1-6,71-1ALIGNMENT PR

3、OCEDURE . 1-4,5 POWER DRIVEN VOLTAGE IDLING CURRENT BALANCE INPUTS CMRR1-2SUBJECT: GRAPHIC SYMBOLSPRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO PRODUCTSA.C. VOLTMETERGOOD EARTH GROUNDSUCH AS THE WATERPIPE. CONDUIT. ETCPLACE THIS PROBEON EACH EXPOSEDMETAL PARTCAUTION : DO NOT ATTEMPT TO MODIFY THIS P

4、RODUCT IN ANY WAY, NEVER PERFORM CUSTOM-IZED INSTALLATIONS WITHOUT MANUFACTURERSAPPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLY VOID THE WARRANTY, BUT MAY LEAD TO YOUR BEING LIABLE FOR ANY RESULTING PROP-ERTY DAMAGE OR USER INJURY.SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE THOROUGHLY FAM

5、ILIAR WITH ALL OF THE FOLLOWING SAFETY CHECKS AND SERVIC-ING GUIDELINES. TO DO OTHERWISE,INCREASES THE RISK OF POTENTIAL HAZARDS AND INJURY TO THE USER.WHILE SERVICING, USE AN ISOLATION TRANS-FORMER FOR PROTECTION FROM A.C. LINESHOCK.SAFETY CHECKSAFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRCTED.

6、 A CHECK SHOULD BE MADE OF THE FOLLOWING.SUBJECT : FIRE & SHOCK HAZARD1.BE SURE THAT ALL COMPONENTS ARE POSI- TIONED IN SUCH A WAY AS TO AVOID POSSIBILITY OF ADJACENT COMPONENT SHORTS.THIS IS ESPE-CIALLY IMPORTANT ON THOSE MODULES WHICH ARE TRANSPORTED TO AND FROM THE REPAIR SHOP.2. NEVER RELEASE A

7、REPAIR UNLESS ALL PROTEC-TIVE DEVICES SUCH AS INSULATORS, BARRIERS, COVERS, SHIELDS, STRAIN RELIEFS, POWER SUPPLY CORDS, AND OTHER HARDWARE HAVE-BEEN REINSTALLED PER ORIGINAL DESIGN. BE SURE THAT THE SAFETY PURPOSE OF THE POLAR-IZED LINE PLUG HAS NOT BEEN DEFEATED.3. SOLDERING MUST BE INSPECTED TO D

8、ISCOVER POSSIBLE COLD SOLDER JOINTS, SOLDER SPLASHES OR SHARP SOLDER POINTS. BE CER-TAIN TO REMOVE ALL LOOSE FOREIGN PARTICLES.4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR DETERIORATION TO PARTS AND COMPONENTS. FOR FRAYED LEADS, DAMAGED INSULATION (INCLUDING A.C. CORD). AND REPLACE IF NECES-5. NO LEA

9、D OR COMPONENT SHOULD TOUCH A RECIVING TUBE OR A RESISTOR RATED AT 1 WATT OR MORE. LEAD TENSION AROUND PROTRUNING METAL SURFACES MUST BE AVOIDED.6. ALL CRITICAL COMPONENTS SUCH AS FUSES, FLAMEPROOF RESISTORS, CAPACITORS, ETC. MUST BE REPLACED WITH EXACT FACTORY TYPES, DO NOT USE REPLACEMENT COMPONEN

10、TS OTHER THAN THOSE SPECIFIED OR MAKE UNRECOM-MENDED CIRCUIT MODIFICATIONS.7. AFTER RE-ASSEMBLY OF THE SET ALWAYS PER-FORM AN A.C. LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OF THE CABINET, (THE CHANNEL SELECTOR KNOB, ANTENNA TERMINALS. HANDLEAND SCREWS) TO BE SURE THE SET IS SAFE TO OPERATE WITHOUT

11、 DANGER OF ELECTRICAL SHOCK. DO NOT USE A LINE ISOLATION TRANS-FORMER DURING THIS TEST USE AN A.C. VOLTME-TER, HAVING 5000 OHMS PER VOLT OR MORE SEN-SITIVITY, IN THE FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT RESISTOR, PARALLELED BY A .15 MFD. 150.V A.C TYPE CAPACITOR BETWEEN A KNOWN GOOD EARTH GR

12、OUND (WATER PIPE, CONDUIT,ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME. MEASURE THE A.C. VOLT-AGE ACROSS THE COMBINATION OF 1500OHM RESISTOR AND .15 MFD CAPACITOR. REVERSE THE A.C. PLUG AND REPEAT A.C. VOLTAGE MEASURE-MENTS FOR EACH EXPOSED METALLIC PART. VOLT-AGE MEASURED MUST NOT EXCEED 75

13、VOLTS R.M.S. THIS CORRESPONDS TO 0.5 MILLIAMP A.C ANY VALUE EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL SHOCK HAZARD AND MUST BE COR-RECTED IMMEDIATELY.THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDEDTO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED

14、 “DANGEROUS VOLTAGE” 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. SERVICING PRECAUTIONS CAUTION:Before

15、servicing the Stereo amplifier 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 any of the safety precautions in this publication, always follow the

16、safety precautions. Remember Safety First: General Servicing Precautions 1. Always unplug the Stereo amplifier AC power cord from the AC power source before: (1) Removing or reinstalling any component, circuit board, module, or any other assembly. (2) Disconnecting or reconnecting any internal elect

17、rical plug or other electrical connection. (3) Connecting a test substitute in parallel with an electrolytic capacitor. Caution: A wrong part substitute or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard. 2. Do not spray chemicals on or near this Stereo a

18、mplifier 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 soft applicator. Unless specified otherwise in this service data

19、, 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 Stereo amplifier and/or any of its electrical assemblies unless all solid-state device heat sinks

20、 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 Disconnect the attachment plug from the AC outlet and turn the power

21、 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 1 M-ohm. Note 1: Accessible Conductive Parts including Metal panels, Input termina

22、ls, 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 of typical Es devices are integrated circuits and some field

23、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 handing any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charg

24、e 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 reason prior to applying power to the unit under test. 2. After removing an electrical assembly equipped with ES device

25、s, 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 antistatic solder removal device. Some solder removal devices not class

26、ified 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 from its protective package until immediately before you are r

27、eady to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil, or comparable conductive material). 7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective materia

28、l 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 replacement ES devices. (Normally harmless motion such as the brus

29、hing 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.)1-3321123 ALIGNMENT PROCEDURE A. POWER DRIVEN VOLTAGE(PSU BOARD) Connect a DC Millivoltmeter to TP601/TP701 1 and 2 pin, then adjust VR601/VR701(6

30、.8kohms) for 0V0.1V. B. IDLING CURRENT(AMP BOARD) 1.Connect a DC Millivoltmeter betweenTP301 2 pins, then adjust VR301 (200ohms) for 7-8mV reading on meter. 2.Connect a DC Millivoltmeter between TP401 2 pins, then adjust VR401 (200ohms) for 7-8mV reading on meter. 3. Watch for 10minutes, to make sur

31、e it is arround 7mVPSU BOARDAMP BOARD(L/R)1-4 C. BALANCE INPUTS CMRR 1.Volum set 0dB, Input 2V/10KHZ common mode sinwave signal at L channel Balance input,Connect a AC Millivoltmeter to preout1L then adjust R565 for lowest output level. 2. Volum set 0dB,Input 2V/10KHZ common mode sinwave signal at R

32、 channel Balance input,Connect a AC Millivoltmeter to preout1R then adjust R564 for lowest output level.1-5Power Amplifier SectionContinuous output power into 4/8 ohms180W (17dBw) (Minimum RMS power per channel, both channels driven, With no more than the rated distortion)Rated distortion (THD)(20Hz

33、 20kHz)0.004%Channel Separation100dB(MAIN IN, 60W Out at 8,1k shorted, 1kHz)Clipping power, 1kHz220W(Maximum continuous power per channel)Dynamic Headroom at 8 ohms4.2dBDynamic power8ohms280W(Maximum short-term power per channel )4ohms480W2ohms785WDamping factor150Signal to noise ratio(refer 1W A-we

34、ighted)100dBSlew rate20V/secT.H.D and SMPTE I.M.0.01% (Distortion from 250mW to rated output)IHF I.M. (CCIF IM) and T.I.M distortion0.005% (From 250mW to rated output)Input impedance20k/680pFInput sensitivity rate power into 8ohms) roF ( 1.38VPower amp gain29dBPreamplifier SectionInput Impedance sin

35、gle-ended input150k /500pFSPECIFICATIONSNAD M3 INTEGRATE AMPLIFIERNote: Specifications are measured in accordance with EIAStandard RS-490 (IHF A-202) for amplifiers1-6balanced input120k /100pFSignal-to-Noise ratio110dB ref 500mV(A-weighted, line In, Pre-Out)Rated distortion (THD)(20Hz 21kHz)0.005%Ch

36、annel Separation110dB(1kHz 2V Line/balanced IN, 2V Pre-Out)Input Sensitivity320mV for 2V outInput Overload Line input Balanced input10VFrequency response(5Hz-70KHz)0.01%?NOYESNO3-4NOYESB Response change properly?Check U112,17V at tone boardCheck TONE_STB,OPSEL_DATAOPSEL_CLK signalTHE END Press Tone

37、Key to change tone setting,measure preout responseYES Level=2V0.1V THD0.03%?NOCheck U109 U209 U111 U211Check OPSEL_STB signalPress Z-2/record key to current input channel then measure output level and THD3-5 DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING 1. SYSTEM 11MHz CLOCKFIG 1-1 2. AT89C51 r

38、eset is high active.FIG 1-23-6 3.volume control DATA and CLOCK4.REC(ZONE) select DATA and CLOCK3-75.Input select DATA and CLOCK3-8AC INLETEMI FILTERSTANDBY RELAYPOWER SWITCHFUSE F901FUSE F903100mA 250VAH: 5A 250VC: 3.15A 350VFUSE F902AH: 5A 250VC: 3.15A 350VR-CORER CHANNELSTANDBYMAINTRANSFORMERL CHA

39、NNELMAINTRANSFORMER TRANSFORMER5V REGULATOR12V RECTIFYB901 IC1B902LOGIC CIRCUITMCU ON PREAMPLOGIC CIRCUITON FPP12V TRIGGERSTANDBYON BALRELAYON PSU20V RECTIFY72V RECTIFYON PSUB606ON PSUHIGH CURRENTRECTIFYPOWER SUPPLYON PSUB603 B60472V REGULATORB606ON PSUISC CIRCUITON PSUD602 D603L CHANNELON L AMPAMPL

40、IFIERB60520V REGULATORB606ON PSUPRE AMPON PRE AMPBALANCE AMPON BALOUTPUT RELAYSL CHANNELON L AMPL CHANNELINPUT RELAYSON PREAMP20V RECTIFY72V RECTIFYON PSUB606ON PSUHIGH CURRENTRECTIFYPOWER SUPPLYON PSUB603 B60472V REGULATORB606ON PSUISC CIRCUITON PSUD602 D603L CHANNELON L AMPAMPLIFIERB60520V REGULAT

41、ORB606ON PSUPRE AMPON PRE AMPBALANCE AMPON BALOUTPUT RELAYSL CHANNELON L AMPL CHANNELINPUT RELAYSON PREAMP1. POWER DISTRIBUTE DIAGRAM3-9BLOCK DIAGRAMSINPUT SELECTORBALANCE AMPDISCCDTUNERINPUT4INPUT5INPUT6BALANCE0/6.5dB SELECTABLE GAINAMP STAGE54dB ATTENUATOR2dB/STEP5dB TONE CONTROL1dB/STEPBIAMP HIGH

42、 PASS FILTER2,2.5,3,3.5dB SELECTABLE GAINAMP STAGE30dB ATTENUATOR10dB/STEPBY PASS, 40, 60, 80, 100HzPRE OUT1PRE OUT2INPUT SELECTORBALANCE AMPDISCCDTUNERINPUT4INPUT5INPUT6BALANCE0/6.5dB SELECTABLE GAINAMP STAGE54dB ATTENUATOR2dB/STEP5dB TONE CONTROL1dB/STEPBIAMP HIGH PASS FILTER2,2.5,3,3.5dB SELECTAB

43、LE GAINAMP STAGE30dB ATTENUATOR10dB/STEPBY PASS, 40, 60, 80, 100HzPRE OUT1PRE OUT2STEREO/MONOSWITCH2. PREAMP SIGNAL PATHLEFT CHANNELRIGHT CHANNEL3-10P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P2.0P2.1P2.2P2.3P2.4P2.5P2.6P2.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7VFDENCODEKEYSEEPROMU83

44、MAX3221 (FPP)RJ45 RS232 SOCKET (REAR PANEL)Q85 Q86 (FPP)IR IN/OUT SOCKET ( REAR PANEL)Q89 inverter(FPP)Protect Circuit (High when Protect)Q91 (PSU)OP91 OPTOISO (PSU)RL91 standby relay (PSU)U84 U85 7400 (FPP)D81 Tri-color LED (FPP)P4.0P4.1P4.2P4.3P4.4P4.5P4.6P4.7P5.0P5.1P5.2P5.3P5.4P5.5P5.6P5.7U108 U

45、113 U208 U213CD4094 (PRE)RL101 . RL112, RL201 . RL212For Input Select and Biamp Filter SwitchQ130 Q131 Q230 Q231 for MuteU105 (PRE) TC9274U110 U210 (PRE)CD4094U104 U107 U204 U207 (PRE) MAX462130dB Attenuator, Q101.Q103, Q201.Q203, 6.5 Gain/ 0.5 Gain SwitchU205 (PRE) TC9274U109 U209 (PRE)TC9274RL301

46、RL302 RL401 RL402OUTPUT RELAYS (LAMP/RAMP)U109 U209 (PRE)TC9274MCUAT89C513. SYSTEM CONTROL PATH3-11CIRCUIT DIAGRAMS 1.POWER AMPLIFIER BOARD3-12C40733P/250VC4021NC40533P/250VC425470pFR40222KR403100R412100R404100R41327KR40527KR414100R406100Q4132SA1837Q4102SA1360Q4092SA1015Q4052SA1015Q4072SA970Q4062SA9

47、70Q4012SA970Q4112SA3423Q4122SC1815Q4082SC1815Q4042SC2240Q4032SC2240Q4022SC2240R40833R42033R45910/2W FSR41510KR42382 FP 1/2WR42139KR41721/1/4W 1%R4191K2 3W 1%R40782R41622KR428300R41110KR41022KR426 100KR424100KR40982 FP 1/2WD4031N4148D4041N4148D4061N4148D4051N4148C408330PQ4142SC4793R4303R3/0.5W FPR432

48、330/0.5W FPR4344K7/3W FPR4383R3/0.5W FPR441330/0.5W FPR4444K7/3W FPR43718R42918R4314R7/FSR4394R7/FSR4451K2 1%R4461K 1%Q415KSC2690Q4172SC4793Q4242SC5200Q4222SC5200Q4182SA1837R4570.05/5WR4560.05/5WR44815R44915R44210KR43310KQ4212SA1943Q4232SA1943C4180.1uF+74V-74V+72V-72VR401470AGNDAGNDAGNDGNDGNDC40310u

49、F/50VC40410uF/50VC411100UF/25VC412100u/25VR43510KR44310KC4160.1uFC4170.1uFC4090.1uFC4100.1u/80VAGNDAGNDQ4262SA970Q425C2240R4646K8C4214u7/50VR46322KR4611KR46256KC42022ND409BV21Q4272SA1943Q4282SC5200SPGNDR4221K2 3W 1%GND231IC402TL431231IC401TL4311VR401200R447220Q4162SA1015C42210uF/80VC42310uF/80VGNDGN

50、DR476220KR47782C41510uF/50VR42539KR4802.2R4822.2R4842.2R4862.2Q4192SA1943Q4202SC5200R4812.2R4832.2R4852.2R4872.2C426470pFR45122GNDR450220KC41910uF/50VQ4372SC4793R4881R4891Q4382SA1837R4911R4901C4280.1uFIC403ATL082DC4271uFR4521MR453680AGNDR4954K7/3W FPR4964K7/3W FPC4291uFR4541MAGNDAGNDR418100L401100uH