NAD-T977-pwr-sm维修电路原理图.pdf

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1、LAUNAMECIVRES LAUNAMECIVRES T977 C/AH DEL:OMT977LAUNAMECIVRES NAD 2012 NAD ELECTRONICS INTERNATIONAL TORONTO T977HA/C RE I F I LPMA L ENNAHC NEVES T977HA/C RE I F I LPMA L ENNAHC NEVES SEVEN CHANNEL AMPLIFIER RadioFans.CN 收音机爱好者资料库 CONTENTS FRONT PANEL/REAR PANEL VIEW 3 SPECIFICATIONS 4 ALIGNMENT P

2、ROCEDURE/ALIGNMENT POINTS 5-6 WIRING DIAGRAM 7 SCHEMATIC DIAGRAM 8-15 PCB LAYOUT 16-21 ELECTRICAL PARTS LIST 22-37 EXPLODED VIEW 38 EXPLODED VIEW PARTS LIST 39 PACKING DIAGRAM 40 SERVICE SAFETY PRECAUTIONS 1. Replacing the Fuses CAUTION: FOR CONTINUED PROTECTION AGAINST THE RISK OF FIRE REPLACE ONLY

3、 WITH SAME TYPE OF FUSE. REFERENCE NO. PART NUMBER DESCRIPTION Rear Panel AH 20-11203-10 MDA T20AL/250V C 20-12103-20 MDA T10AL/250V AMP Board F101/F102 20-12632-00 T6.3AL/250V PSU Board F201-F204 20-12162-01 T1.6AL/250V NOTE: *AH : North American version only *C : European version only 2. Safety-ch

4、eck out (North American model only) Before returning the product to the customer, make leakage current or resistance measurements to determine that exposed parts are acceptably insulated from the supply circuit. Parts marked with the symbol are critical with regard to the risk of fire and electric s

5、hock.Replace only parts recommended by the manufacturer. - 2 - RadioFans.CN 收音机爱好者资料库 - 3 - RadioFans.CN 收音机爱好者资料库 - 4 - SPECIFICATIONS CONTINUOUS AVERAGE POWER 140 W (21.5 dBW) OUTPUT INTO 8 OHMS OR 4 OHMS (Min. power per channel, 20 Hz 20 kHz, both channels driven, with no more than rated distor

6、tion) Rated Distortion 0.03% (THD 20 Hz 20 kHz) Clipping power 170 W(22.3 dBW) (maximum continuous power per channel). IHF dynamic power (Maximum short term power per channel) 8 ohms: 230 W (23.6 dBW) 4 ohms: 390 W (25.9 dBW) 2 ohms: 450 W (26.5 dBW) Time to go to Standby mode at no input signal 30

7、minutes Damping factor 300 (ref. 8 ohms 50Hz) Input Impedance R = 1 Mohms C = 180 pF Input sensitivity (for rated output into 8 ohms) 1180mV+/-50mV Voltage gain 29 dB Frequency response 20 Hz 20 kHz 0.2 dB - 3dB at 3 Hz/100 kHz Signal / Noise ratio, A-weighted 96 dB ref. 1 W 125 dB ref. 140W DIMENSI

8、ONS AND WEIGHTS Net Weight 32.3 kg (71.2 Ib) Shipping Weight 36.5 kg (80.5 Ib) Dimension (WHD) 435 194 476mm RadioFans.CN 收音机爱好者资料库 ALIGNMENT PROCEDURE (T977) A. THERMAL SENSE ADJUSTMENT This adjustment should be always done when the T977 is cool condition. (That means the temperature inside the un

9、it should be almost same as the ambient temperature. Connector P208B that connects the transformer and power board should be removed to avoid that the Idling current heats up the unit excessively) At ambient temperature of 25 C degrees and when the unit is just turned on (still in cool condition), a

10、djust the pot RV103(as marked as “Thermal Sense ADJ” in below drawing) for a voltage between the THERMAL TEST POINT and AGND to be 750mV+/-10mV. If the ambient temperature is different, the voltage setting should be changed by 20mV per degree difference. So at 20C degrees, the voltage should be 850m

11、V+/-10mV; and at 30C degrees, the voltage should be 650mV+/-10mV, etc. B. DC OFFSET VOLTAGE The DC OFFSET between OFFSET Test Point and AGND must be within 0+/-3mV. If its found to be out of this range, change the TL084BCD to one selected for low offset voltage to meet the requirement. C. IDLING CUR

12、RENT The idling current in the output stage of the poweramp should be set to 40mA+/-10mA per pnp-npn transistor pair( This means the mid point voltage is 17.6mV with down limit of 13.2mV and up limit of 22mV). The alignment procedure is: At first, adjust RV102 (Marked as “Idling Current ADJ” in the

13、drawing below) for a voltage of 17.6mV +/- 1mV between Test point 1 and 2. Then preheat the unit for 5 minutes, let idling current settled and then readjust to 17.6mV +/- 1mV. Pls note: 1. The idling current must be adjusted when all modules are assembled into the unit. 2. Though the idling current

14、is set as 17.6mV +/-1mV during the adjustment, due to the influence of varied ambient temperature and mains voltage etc., the idling current will drift after some time. During the normal checking of idling current in the service field, its acceptable as long as the voltage is in the range of 13.2mV2

15、2.0mV. D. ISC SENSITIVITY The ISC sensing voltage can allow 0mV+/-50mV. But, for the alignment process in our factory, we tighten the limit to 0mV+/-10mV. That is to adjust Pot RV104 (as marked as “ISC SENSE ADJ” in the below drawing) to get a voltage between the “ISC SENSE TEST POINT” and AGND to b

16、e 0mV+/-10mV. (Pls note the ISC should be adjusted when all modules are plugged in. Its not possible to get 0mV +/-10mV if any of the modules are removed.) E. Fan Cut Off Point Adjustment Check the Fan sense voltage first. Turn Pot RV201 to the end clockwise and confirm TP2 of J201 is in negative vo

17、ltage. Run the unit to heat it up and drive the fan to start turning, - 5 - RadioFans.CN 收音机爱好者资料库 for example, all 7 channels at 50W/4ohms for 10 minutes or 5 minutes or even less (as long as the fan can starts turning). Turn off the signal but still keep the unit operating for 1 minute. Then run

18、all 7 channels at 1kHz, 0.25W at 4 ohms load, monitor the voltage at TP1 of Pot RV201. Adjust RV201 to get the voltage from negative to positive to ensure that the Fans are turned off. Then run all 7 channels at 1kHz, 0.5W at 4 ohms load, monitor if the voltage at TP1 of Pot RV201 is negative, if no

19、t, adjust Pot RV201 just to the point that TP1 changes from positive to negative (to get the fans just start turning). Finally, turn off the signal and monitor if fans stop turning within about 30s Max. - 6 - RadioFans.CN 收音机爱好者资料库 AGND +62V +62V -62V -62V AGND AGND AGND ISCTRIG AC OFF SEN PROTECT

20、-68V +68V -18V +18V SC PNP SC NPN AGND +62V +62V -62V -62V AGND AGND AGND ISCTRIG AC OFF SEN PROTECT -68V +68V -18V +18V SC PNP SC NPN AGND +62V +62V -62V -62V AGND AGND AGND ISCTRIG AC OFF SEN PROTECT -68V +68V -18V +18V SC PNP SC NPN AGND +62V +62V -62V -62V AGND AGND AGND ISCTRIG AC OFF SEN PROTE

21、CT -68V +68V -18V +18V SC PNP SC NPN AGND +62V +62V -62V -62V AGND AGND AGND ISCTRIG AC OFF SEN PROTECT -68V +68V -18V +18V SC PNP SC NPN AGND +62V +62V -62V -62V AGND AGND AGND ISCTRIG AC OFF SEN PROTECT -68V +68V -18V +18V SC PNP SC NPN AGND +62V +62V -62V -62V AGND AGND AGND ISCTRIG AC OFF SEN PR

22、OTECT -68V +68V -18V +18V SC PNP SC NPN SCN_4 SCP_4 +18V -18V +68V -68V PROT1 SEN1 ACOFF +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 STBY STBY +8V +8V PROT4 PROT3 PROT5 PROT2 PROT6 PROT1 PROT7 DGND DGND SCLED SCLED AGND SEN1 SEN2 SEN7 SEN3 SEN6 SEN4 AGND SEN5 ISCTRIG_1 ISCTRIG_2 I

23、SCTRIG_3 ISCTRIG_4 ISCTRIG_5 ISCTRIG_6 ISCTRIG_7 DGND SCN_4 SCP_4 +18V -18V +68V -68V PROT1 SEN1 ACOFF +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 SCN_4 SCP_4 +18V -18V +68V -68V PROT1 SEN1 ACOFF +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 SCN_4 SCP_4 +18V -18V

24、+68V -68V PROT1 SEN1 ACOFF +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 SCN_4 SCP_4 +18V -18V +68V -68V PROT1 SEN1 ACOFF +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 SCN_4 SCP_4 +18V -18V +68V -68V PROT1 SEN1 ACOFF +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGN

25、D4A ISCTRIG_1 SCN_4 SCP_4 +18V -18V +68V -68V PROT1 SEN1 ACOFF +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 STBY +8V DGND SCLED SCN_3 SCN_4 SCP_3 SCP_4 +62V_3 -62V_3 +62V_4 -62V_4 DGND -18V +18V ACOFF +70V -70V FAN3 FAN2 FAN1 DGND FAN1 DGND FAN2 DGND DGND FAN3 +12VD PROT1 PROT2 PRO

26、T3 PROT4 PROT5 PROT6 PROT7 SCLED DGND +5VD STBYLED 15V 15V AGND1 64V 64V 38V 38V AGND2 53V 53V ON/OFF STBY DGND -18V +18V ACOFF +70V -70V FAN3 FAN2 FAN1 DGND STBY +8V DGND SCLED SCN_3 SCN_4 SCP_3 SCP_4 +62V_3 -62V_3 +62V_4 -62V_4 PROT1 STBYLED PROT3 +12VD PROT2 PROT4 +5VD PROT6 PROT5 SCLED PROT7 DGN

27、D ON/OFF STBY STBY STBY +8V +8V PROT4 PROT3 PROT5 PROT2 PROT6 PROT1 PROT7 DGND DGND SCLED SCLED AGND SEN1 SEN2 SEN7 SEN3 SEN6 SEN4 AGND SEN5 ISCTRIG_1 ISCTRIG_2 ISCTRIG_3 ISCTRIG_4 ISCTRIG_5 ISCTRIG_6 ISCTRIG_7 DGND +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 +62V_4A +62V_4A -62V_

28、4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 +62V_4A +62V_4A -62V_4A -62V_4A AGND4A AGND4A AGND4A ISCTRIG_1 +5VD RELAY DGND AC SENS TO P611BTO P604B TO P612BTO P605B TO P613B TO P606B TO P614BTO P607B TO P615BTO P608B TO P616B TO P609B TO P

29、617B TO P610B STANDBY BOARDMAIN TRANSFORMER DISPLAY BOARD THERMAL PROTECT BOARD POWER SUPPLY BOARD CONNECTION BOARD POWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARD FROM P204BFROM P205B FROM P203B TO P

30、603BTO P602BTO P601B TRIGGER BOARD TO P401B FROM P618B FROM P201A TO P620B CHANNEL 1CHANNEL 2CHANNEL 3CHANNEL 4CHANNEL 5CHANNEL 6CHANNEL 7 TO CH1 P101A TO CH1 P102A TO CH2 P101ATO CH2 P102A TO CH3 P101ATO CH3 P102A TO CH4 P101A TO CH4 P102A TO CH5 P101ATO CH5 P102A TO CH6 P101A TO CH6 P102A TO CH7 P

31、101ATO CH7 P102A FROM P202A TO FAN1TO FAN2TO FAN3 TO P301A TO P506B FROM P207A FROM P2AFROM P1A FROM AC INLETFROM FUSE TO P4ATO P3A TO J901 FROM J204 TO P619B FROM P206B TO P209BTO P208B TO P504BTO P505B 120 deg thermal breaker P608B MOLEX 26-01-1099 P608B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P102A MO

32、LEX 41662 P102A MOLEX 41662 1 2 3 4 5 6 7 8 9 P613B MOLEX 26-01-1099 P613B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 TP901 115deg THERMAL CIRCUIT BREAKER TP901 115deg THERMAL CIRCUIT BREAKER 12 P506BP506B 1 2 3 4 P618B 12PIN2.0-A580B P618B 12PIN2.0-A580B 2 3 4 1 5 6 7 8 9 10 11 12 R1A1 47 R1A1 47 J102 BIND

33、DING POST J102 BINDDING POST 1 2 J102 BINDDING POST J102 BINDDING POST 1 2 CONTACTS UPSIDE P602B MOLEX 52207-1690 CONTACTS UPSIDE P602B MOLEX 52207-1690 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1718 P101A MOLEX 41662 P101A MOLEX 41662 1 2 3 4 5 6 7 8 9 R1A 47 R1A 47 J102 BINDDING POST J102 BINDDING PO

34、ST 1 2 P621B 2PIN2.54-C P621B 2PIN2.54-C 1 2 W1W1 P101A MOLEX 41662 P101A MOLEX 41662 1 2 3 4 5 6 7 8 9 P3A MOLEX 44441-2005 P3A MOLEX 44441-2005 1 2 3 4 5 P610B MOLEX 26-01-1099 P610B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P101A MOLEX 41662 P101A MOLEX 41662 1 2 3 4 5 6 7 8 9 P2A MOLEX_51144-0200 P2A M

35、OLEX_51144-0200 1 2 P607B MOLEX 26-01-1099 P607B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 R1A1 47 R1A1 47 F1 FUSE HOLDER F1 FUSE HOLDER P207AP207A 2 3 4 1 P4A MOLEX_51144-0500 P4A MOLEX_51144-0500 1 2 3 4 5 J102 BINDDING POST J102 BINDDING POST 1 2 P619B MOLEX 26-01-1089 P619B MOLEX 26-01-1089 1 2 3 4 5 6

36、 7 8 P101A MOLEX 41662 P101A MOLEX 41662 1 2 3 4 5 6 7 8 9 J901 2PIN2.54 J901 2PIN2.54 1 2 P401B 12PIN2.0-C P401B 12PIN2.0-C 1 2 3 4 5 6 7 8 9 10 11 12 P616B MOLEX 26-01-1099 P616B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P202A MOLEX 41662 P202A MOLEX 41662 1 2 3 4 5 6 7 8 J102 BINDDING POST J102 BINDDING

37、 POST 1 2 R1A1 47 R1A1 47 W2W2 P502B KY250 P502B KY250 1 2 P201A MOLEX 41662 P201A MOLEX 41662 1 2 3 4 5 6 7 8 P205B FLEX CONNECTOR DIP16 P205B FLEX CONNECTOR DIP16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 TP904 115deg THERMAL CIRCUIT BREAKER TP904 115deg THERMAL CIRCUIT BREAKER 12 J101 RCA J101 RCA 1

38、 2 P617B MOLEX 26-01-1099 P617B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P615B MOLEX 26-01-1099 P615B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 TP903 115deg THERMAL CIRCUIT BREAKER TP903 115deg THERMAL CIRCUIT BREAKER 12 P101A MOLEX 41662 P101A MOLEX 41662 1 2 3 4 5 6 7 8 9 FAN1 FAN FAN1 FAN 1 2 P102A MOLEX 4166

39、2 P102A MOLEX 41662 1 2 3 4 5 6 7 8 9 P611B MOLEX 26-01-1099 P611B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 FAN3 FAN FAN3 FAN 1 2 W3W3 P209B 5PIN3.96-C P209B 5PIN3.96-C 1 2 4 5 3 J102 BINDDING POST J102 BINDDING POST 1 2 P204B FLEX CONNECTOR DIP16 P204B FLEX CONNECTOR DIP16 1 2 3 4 5 6 7 8 9 10 11 12 13 1

40、4 15 16 R1A1 47 R1A1 47 P622B 2PIN2.54-C P622B 2PIN2.54-C 1 2 J101 RCA J101 RCA 1 2 P1A MOLEX_44441-2004 P1A MOLEX_44441-2004 1 2 3 4 P101A MOLEX 41662 P101A MOLEX 41662 1 2 3 4 5 6 7 8 9 P102A MOLEX 41662 P102A MOLEX 41662 1 2 3 4 5 6 7 8 9 J204 2PIN2.54 J204 2PIN2.54 1 2 R1A11 47 R1A11 47 P623B 2P

41、IN2.54-C P623B 2PIN2.54-C 1 2 t TR1 T973MKII-B MAIN TRANSFORMER t TR1 T973MKII-B MAIN TRANSFORMER 1 2 14 3 4 5 6 7 8 9 10 11 13 15 16 17 P605B MOLEX 26-01-1099 P605B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P505B MOLEX 43160-2104 P505B MOLEX 43160-2104 1 2 3 4 J102 BINDDING POST J102 BINDDING POST 1 2 P10

42、2A MOLEX 41662 P102A MOLEX 41662 1 2 3 4 5 6 7 8 9 P101A MOLEX 41662 P101A MOLEX 41662 1 2 3 4 5 6 7 8 9 P504B 2PIN3.96-C P504B 2PIN3.96-C 1 2 R1A1 47 R1A1 47 U4 AC INLET U4 AC INLET P102A MOLEX 41662 P102A MOLEX 41662 1 2 3 4 5 6 7 8 9 J101 RCA J101 RCA 1 2 P301A 12P2.0-A350B P301A 12P2.0-A350B 1 2

43、 3 4 5 6 7 8 9 10 11 12 P206B 12PIN2.0-C P206B 12PIN2.0-C 1 2 3 4 5 6 7 8 9 10 11 12 J101 RCA J101 RCA 1 2 FAN2 FAN FAN2 FAN 1 2 J107 RCA J107 RCA 1 2 P614B MOLEX 26-01-1099 P614B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 CONTACTS UPSIDE P601B MOLEX 52207-1690 CONTACTS UPSIDE P601B MOLEX 52207-1690 1 2 3 4

44、 5 6 7 8 9 10 11 12 13 14 15 16 1718 P604B MOLEX 26-01-1099 P604B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P102A MOLEX 41662 P102A MOLEX 41662 1 2 3 4 5 6 7 8 9 J101 RCA J101 RCA 1 2 P102A MOLEX 41662 P102A MOLEX 41662 1 2 3 4 5 6 7 8 9 P620B MOLEX 26-01-1089 P620B MOLEX 26-01-1089 1 2 3 4 5 6 7 8 P603B 1

45、0PIN2.54-C P603B 10PIN2.54-C 1 2 3 4 5 6 7 8 9 10 1112 P606B MOLEX 26-01-1099 P606B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P208B MOLEX 43160-2105 P208B MOLEX 43160-2105 1 2 3 4 5 J101 RCA J101 RCA 1 2 TP902 115deg THERMAL CIRCUIT BREAKER TP902 115deg THERMAL CIRCUIT BREAKER 12 P612B MOLEX 26-01-1099 P61

46、2B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P501B PCFS2508 P501B PCFS2508 1 2 P609B MOLEX 26-01-1099 P609B MOLEX 26-01-1099 1 2 3 4 5 6 7 8 9 P203B 10PIN2.54-A60B P203B 10PIN2.54-A60B 2 3 4 1 5 6 7 8 9 10 - 7 - WIRING DIAGRAM RadioFans.CN 收音机爱好者资料库 INPUT OFFSET ISCTRIG +62V SEN 62V TESTPOINT 5 +12V -12V

47、+12V -12V +12V -12V -12V OFFSET +62V SEN ISC 62V INPUT TP5 SC NPN SC PNP /1/2W /1% TEMP SEN All Polyester capacitors are 63V unless noted. All Elec. capacitors are 50V unless noted. All Resistor are 1/6W RJ13 unless noted. /1% /1% /1% /3W /1% /1% INPUT BUFFER /16V ISC COMPARATOR /1% I/V /1/2W R112 976 R112 976 C115 1nF C115 1nF R107 1K R107 1K + C148 1uF + C148 1uF + - IC104B TL082CP + - IC104B TL08