NAD-T975-pwr-sm 维修电路原理图.pdf

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1、? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?RadioFans.CN 收音机爱 好者资料库CONTENTSFRONT PANEL/REAR PANELVIEW? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?3SPECIFICATIONS? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

2、? ? ? ? ? ? ? 4ALIGNMENT PROCEDURE/ALIGNMENT POINTS? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 5-6WIRING DIAGRAM? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?7SCHEMATIC DIAGRAM? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

3、 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?8-15PCB LAYOUT? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 16-23ELECTRICALPARTS LIST? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

4、 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?24-37EXPLODED VIEW? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 38EXPLODED VIEW PARTS LIST? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?39PACKING DIA

5、GRAM? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?40SERVICE SAFETY PRECAUTIONS1. Replacing the FusesCAUTION: FOR CONTINUED PROTECTION AGAINST THE RISK OF FIREREPLACE ONLY WITH SAME TYPE OF FUSE.REFERENCE NO.PART NUMBERDESCRIPTIONRear

6、 PanelAH20-11203-10MDAT20AL/250VC20-12103-20MDAT10AL/250VAMP BoardF101/F10220-12632-00T6.3AL/250VPSU BoardF201-F20420-12162-01T1.6AL/250VNOTE:*AH : North American version only*C: European version only2. Safety-check out (North American model only)Before returning the product to the customer, make le

7、akage current orresistance measurements to determine that exposed parts are acceptablyinsulated from the supply circuit.Parts marked with the symbolare critical with regard to the risk of fire andelectric shock.Replace only parts recommended by the manufacturer.- 2 -RadioFans.CN 收音机爱 好者资料库? ? ? ? ?

8、? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?- 3 - 4 -SPECIFICATIONSCONTINUOUS AVERAGE POWER?140 W (21.5 dBW)OUTPUT INTO 8 OHMS OR 4 OHMS(Min. power per channel, 20 Hz 20 kHz, bothchannels driven, with no more than rateddistortion)Rated Distortion?0.03

9、%(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:?220 W (23.4 dBW)4 ohms:?385 W (25.9 dBW)2 ohms:?450 W (26.5 dBW)Damping factor300(ref. 8 ohms 50Hz)Input ImpedanceR = 1 MohmsC = 180 pFInput sensitiv

10、ity (for rated output into 8 ohms)1180mV+/-50mVVoltage gain29 dBFrequency response 20 Hz 20 kHz?0.2 dB- 3dB at 3 Hz/100 kHzSignal / Noise ratio, A-weighted96 dB ref. 1 W125 dB ref. 140WDIMENSIONS AND WEIGHTSNet Weight31 kg (68.0 Ib)Shipping Weight33 kg (72 Ib)Dimension (WHD)435 180 450mmALIGNMENT PR

11、OCEDURE (T975)A. THERMAL SENSE ADJUSTMENTThis adjustment should be always done when the T975 is in a cool condition. (That means thetemperature inside the unit should be almost same as the ambient temperature.)Connector P208B that connects the transformer and power board should be removed toavoid th

12、e Idling current heating up the unit excessively) At ambient temperature of 25 Cdegrees and when the unit is just turned on (still in cool condition), adjust the potRV103 (as marked as “Thermal Sense ADJ” in below drawing) for a voltage between theTHERMAL TEST POINT and AGND to be 750mV+/-10mV. If t

13、he ambient temperature isdifferent, the voltage setting should be changed by 20mV per degree C difference. So at20C degrees, the voltage should be 850mV+/-10mV; and at 30C degrees, the voltageshould be 650mV+/-10mV, etc.B. DC OFFSET VOLTAGEThe DC OFFSET between OFFSET Test Point and AGND must be wit

14、hin 0+/-3mV. If itsfound to be out of this range, change the TL084BCD to one selected for low offset voltageto meet the requirement.C. IDLING CURRENTThe idling current in the output stage of the poweramp should be set to 40mA+/-10mAper pnp-npn transistor pair (This means the mid point voltage is 17.

15、6mV with down limit of13.2mV and up limit of 22mV). The alignment procedure is: At first, adjust RV102 (Markedas “Idling Current ADJ” in the drawing below) for a voltage of 17.6mV +/- 1mV betweenTest point 1 and 2. Then preheat the unit for 5 minutes, let idling current settled and thenreadjust to 1

16、7.6mV +/- 1mV.Pls note:1.The idling current must be adjusted when all modules are assembled into the unit.2.Though the idling current is set as 17.6mV +/-1mV during the adjustment, due to theinfluence of varied ambient temperature and mains voltage etc., the idling current will driftafter some time.

17、 During the normal checking of idling current in the service field, itsacceptable as long as the voltage is in the range of 13.2mV22.0mV.D. ISC SENSITIVITYThe ISC sensing voltage range is 0mV+/-50mV. But, for the alignment process duringproduction, we tighten the limit to 0mV+/-10mV. That is to adju

18、st Pot RV104 (as marked as“ISC SENSE ADJ” in the below drawing) to get a voltage between the “ISC SENSE TESTPOINT” and AGND to be 0mV+/-10mV.(Please note the ISC should be adjusted when all modules are plugged in. Its not possible to get0mV +/-10mV if any of the modules are removed.)E. Fan Cut Off P

19、oint AdjustmentCheck the Fan sense voltage first. Turn Pot RV201 (on the power supply board) to the end clockwiseand confirm TP2 of J201 is negative voltage. Run the unit to heat it up and to start turning the fan.- 5 -For example; all 7 channels at 50W/4 ohms for 10 minutes or 5 minutes or even les

20、s (aslong as the fan can starts turning). Turn off the signal but still keep the unit operating for 1minute. Then run all 7 channels at 1kHz, 0.25W at 4 ohms load, monitor the voltage atTP1 of Pot RV201. Adjust RV201 to get the voltage from negative to positive to ensurethat the Fans are turned off.

21、 Then run all 7 channels at 1kHz, 0.5W at 4 ohmsload, monitor if the voltage at TP1 of Pot RV201 is negative, if not, adjust Pot RV201 justto 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

22、 about 30s Maximum.- 6 -AGND+62V+62V-62V-62VAGNDAGNDAGNDISCTRIGAC OFFSENPROTECT-68V+68V-18V+18VSC PNPSC NPNAGND+62V+62V-62V-62VAGNDAGNDAGNDISCTRIGAC OFFSENPROTECT-68V+68V-18V+18VSC PNPSC NPNAGND+62V+62V-62V-62VAGNDAGNDAGNDISCTRIGAC OFFSENPROTECT-68V+68V-18V+18VSC PNPSC NPNAGND+62V+62V-62V-62VAGNDAGN

23、DAGNDISCTRIGAC OFFSENPROTECT-68V+68V-18V+18VSC PNPSC NPNAGND+62V+62V-62V-62VAGNDAGNDAGNDISCTRIGAC OFFSENPROTECT-68V+68V-18V+18VSC PNPSC NPNAGND+62V+62V-62V-62VAGNDAGNDAGNDISCTRIGAC OFFSENPROTECT-68V+68V-18V+18VSC PNPSC NPNAGND+62V+62V-62V-62VAGNDAGNDAGNDISCTRIGAC OFFSENPROTECT-68V+68V-18V+18VSC PNPS

24、C NPNSCN_4SCP_4+18V-18V+68V-68VPROT1SEN1ACOFF+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1STBYSTBY+8V+8VPROT4PROT3PROT5PROT2PROT6PROT1PROT7DGNDDGNDSCLEDSCLEDAGNDSEN1SEN2SEN7SEN3SEN6SEN4AGNDSEN5ISCTRIG_1ISCTRIG_2ISCTRIG_3ISCTRIG_4ISCTRIG_5ISCTRIG_6ISCTRIG_7DGNDSCN_4SCP_4+18V-18V+68V-68VPROT

25、1SEN1ACOFF+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1SCN_4SCP_4+18V-18V+68V-68VPROT1SEN1ACOFF+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1SCN_4SCP_4+18V-18V+68V-68VPROT1SEN1ACOFF+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1SCN_4SCP_4+18V-18V+68V-68VPROT1SEN1ACOFF+62V_

26、4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1SCN_4SCP_4+18V-18V+68V-68VPROT1SEN1ACOFF+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1SCN_4SCP_4+18V-18V+68V-68VPROT1SEN1ACOFF+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1STBY+8VDGNDSCLEDSCN_3SCN_4SCP_3SCP_4+62V_3-62V_3+62V_4-62V_4

27、DGND-18V+18VACOFF+70V-70VFAN3FAN2FAN1DGNDFAN1DGNDFAN2DGNDDGNDFAN3+12VDPROT1PROT2PROT3PROT4PROT5PROT6PROT7SCLEDDGND+5VDSTBYLEDACINI/VDGNDACOUT+5VDRELAY15V15VAGND164V64V38V38VAGND253V53VON/OFFSTBYDGND-18V+18VACOFF+70V-70VFAN3FAN2FAN1DGNDSTBY+8VDGNDSCLEDSCN_3SCN_4SCP_3SCP_4+62V_3-62V_3+62V_4-62V_4DGNDS

28、TBYLEDGREENPROT1STBYLEDPROT3+12VDPROT2PROT4+5VDPROT6PROT5SCLEDPROT7DGNDDGNDSTBYLEDGREENON/OFFSTBYSTBYSTBY+8V+8VPROT4PROT3PROT5PROT2PROT6PROT1PROT7DGNDDGNDSCLEDSCLEDAGNDSEN1SEN2SEN7SEN3SEN6SEN4AGNDSEN5ISCTRIG_1ISCTRIG_2ISCTRIG_3ISCTRIG_4ISCTRIG_5ISCTRIG_6ISCTRIG_7DGND+62V_4A+62V_4A-62V_4A-62V_4AAGND4

29、AAGND4AAGND4AISCTRIG_1+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1+62V_4A+62V_4A-62V_4A-62V_4AAGND4AAGND4AAGND4AISCTRIG_1TO P611BTO P604BTO P612BTO P605BTO P613BTO P606BTO P614BTO P607BTO P615BTO P608BTO P616BTO P609BTO P617BTO P610BP

30、OWER SWITCH BOARDSTANDBY BOARDMAIN TRANSFORMERDISPLAY BOARDPOWER LED BOARDTHERMAL PROTECT BOARDPOWER SUPPLY BOARDCONNECTION BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDPOWERAMP MODULE BOARDFROM P204BFROM P205BFROM

31、 P203BTO P603BTO P602BTO P601BTRIGGER BOARDTO P401BFROM P618BFROM P201ATO P620BCHANNEL 1CHANNEL 2CHANNEL 3CHANNEL 4CHANNEL 5CHANNEL 6CHANNEL 7TO CH1 P101ATO CH1 P102ATO CH2 P101ATO CH2 P102ATO CH3 P101ATO CH3 P102ATO CH4 P101ATO CH4 P102ATO CH5 P101ATO CH5 P102ATO CH6 P101ATO CH6 P102ATO CH7 P101ATO

32、 CH7 P102AFROM P202ATO FAN1TO FAN2TO FAN3TO P301ATO P506BFROM P207AFROM P801AFROM P2AFROM P1ATO P503BFROM AC INLETFROM FUSETO P4ATO P3ATO J901FROM J204TO P619BFROM P206BFROM P302TO P701ATO P209BTO P208BTO P504BTO P505B120 deg thermal breakerP623B2PIN2.54-CP623B2PIN2.54-C12P301A12P2.0-A350BP301A12P2.

33、0-A350B123456789101112P401B12PIN2.0-CP401B12PIN2.0-C123456789101112P609BMOLEX 26-01-1099P609BMOLEX 26-01-1099123456789P101AMOLEX 41662P101AMOLEX 41662123456789P604BMOLEX 26-01-1099P604BMOLEX 26-01-1099123456789J102BINDDING POSTJ102BINDDING POST12P209B5PIN3.96-CP209B5PIN3.96-C12453P616BMOLEX 26-01-10

34、99P616BMOLEX 26-01-1099123456789J101RCAJ101RCA12P619BMOLEX 26-01-1089P619BMOLEX 26-01-108912345678tTR1T973MKII-B MAIN TRANSFORMERtTR1T973MKII-B MAIN TRANSFORMER12143456789101113151617P612BMOLEX 26-01-1099P612BMOLEX 26-01-1099123456789P611BMOLEX 26-01-1099P611BMOLEX 26-01-1099123456789J101RCAJ101RCA1

35、2CONTACTS UPSIDEP602BMOLEX 52207-1690CONTACTS UPSIDEP602BMOLEX 52207-1690123456789101112131415161718TP902115deg THERMAL CIRCUIT BREAKERTP902115deg THERMAL CIRCUIT BREAKER12P206B12PIN2.0-CP206B12PIN2.0-C123456789101112TP904115deg THERMAL CIRCUIT BREAKERTP904115deg THERMAL CIRCUIT BREAKER12FAN3FANFAN3

36、FAN12R1A147R1A147TP901115deg THERMAL CIRCUIT BREAKERTP901115deg THERMAL CIRCUIT BREAKER12J2042PIN2.54J2042PIN2.5412P203B10PIN2.54-A60BP203B10PIN2.54-A60B23415678910P622B2PIN2.54-CP622B2PIN2.54-C12P621B2PIN2.54-CP621B2PIN2.54-C12J102BINDDING POSTJ102BINDDING POST12P617BMOLEX 26-01-1099P617BMOLEX 26-0

37、1-1099123456789J101RCAJ101RCA12P613BMOLEX 26-01-1099P613BMOLEX 26-01-1099123456789D701L-519EGWD701L-519EGWCGRTP903115deg THERMAL CIRCUIT BREAKERTP903115deg THERMAL CIRCUIT BREAKER12P102AMOLEX 41662P102AMOLEX 41662123456789R1A147R1A147J102BINDDING POSTJ102BINDDING POST12P101AMOLEX 41662P101AMOLEX 416

38、62123456789P205BFLEX CONNECTOR DIP16P205BFLEX CONNECTOR DIP1612345678910111213141516J101RCAJ101RCA12P201AMOLEX 41662P201AMOLEX 4166212345678P501BPCFS2508P501BPCFS250812P4AMOLEX_51144-0500P4AMOLEX_51144-050012345P204BFLEX CONNECTOR DIP16P204BFLEX CONNECTOR DIP1612345678910111213141516J102BINDDING POS

39、TJ102BINDDING POST12P101AMOLEX 41662P101AMOLEX 41662123456789J9012PIN2.54J9012PIN2.5412P605BMOLEX 26-01-1099P605BMOLEX 26-01-1099123456789FAN2FANFAN2FAN12J102BINDDING POSTJ102BINDDING POST12R1A147R1A147P505BMOLEX 43160-2104P505BMOLEX 43160-21041234CONTACTS UPSIDEP601BMOLEX 52207-1690CONTACTS UPSIDEP

40、601BMOLEX 52207-1690123456789101112131415161718P620BMOLEX 26-01-1089P620BMOLEX 26-01-108912345678P2AMOLEX_51144-0200P2AMOLEX_51144-020012U4AC INLETU4AC INLETP801A2PIN2.54-A100BP801A2PIN2.54-A100B21P615BMOLEX 26-01-1099P615BMOLEX 26-01-1099123456789R1A1147R1A1147W3W3P618B12PIN2.0-A580BP618B12PIN2.0-A

41、580B234156789101112F1FUSE HOLDERF1FUSE HOLDERJ101RCAJ101RCA12P606BMOLEX 26-01-1099P606BMOLEX 26-01-1099123456789J102BINDDING POSTJ102BINDDING POST12J107RCAJ107RCA12P607BMOLEX 26-01-1099P607BMOLEX 26-01-1099123456789P603B10PIN2.54-CP603B10PIN2.54-C123456789101112S801SDDLB1027U-RNS801SDDLB1027U-RN12P6

42、08BMOLEX 26-01-1099P608BMOLEX 26-01-1099123456789P102AMOLEX 41662P102AMOLEX 41662123456789P101AMOLEX 41662P101AMOLEX 41662123456789P102AMOLEX 41662P102AMOLEX 41662123456789J101RCAJ101RCA12R1A47R1A47P101AMOLEX 41662P101AMOLEX 41662123456789P503B2PIN2.54-CP503B2PIN2.54-C12P208BMOLEX 43160-2105P208BMOL

43、EX 43160-210512345W2W2P1AMOLEX_44441-2004P1AMOLEX_44441-20041234P701A3PIN2.54-CP701A3PIN2.54-C123FAN1FANFAN1FAN12P614BMOLEX 26-01-1099P614BMOLEX 26-01-1099123456789P102AMOLEX 41662P102AMOLEX 41662123456789J102BINDDING POSTJ102BINDDING POST12R1A147R1A147P504B2PIN3.96-CP504B2PIN3.96-C12R1A147R1A147P10

44、2AMOLEX 41662P102AMOLEX 41662123456789P610BMOLEX 26-01-1099P610BMOLEX 26-01-1099123456789P101AMOLEX 41662P101AMOLEX 41662123456789P101AMOLEX 41662P101AMOLEX 41662123456789P202AMOLEX 41662P202AMOLEX 4166212345678P3023PIN2.54-A100BP3023PIN2.54-A100B231P3AMOLEX 44441-2005P3AMOLEX 44441-200512345P102AMO

45、LEX 41662P102AMOLEX 41662123456789P207A6PIN2.54-A100BP207A6PIN2.54-A100B234156P102AMOLEX 41662P102AMOLEX 41662123456789P502BKY250P502BKY25012P506B6PIN2.0-CP506B6PIN2.0-C123456W1W1- 7 -WIRING DIAGRAMINPUTOFFSETISCTRIG+62VSEN62VTESTPOINT 5+12V-12V+12V-12V+12V-12V-12VOFFSET+62VSENISC62VINPUTTP5SC NPNSC

46、 PNP/1KV/1/2W/1%TEMP SENAll Polyester capacitors are 63V unless noted.All Elec. capacitors are 50V unless noted.All Resistor are 1/6W RJ13 unless noted./1KV/1KV/1KV/1KV/1%/1%/1%/3W/1%/1%INPUT BUFFER/16V/1KVISC COMPARATOR/1%I/V/1/2W/1KV/1KV/1KVR1A41KR1A41KR186390KR186390KR1E82.2megR1E82.2megR1E3100R1

47、E3100R1C21KR1C21K+C1641uF+C1641uFR1A0470R1A0470R1E2100R1E2100C174470pFC174470pFR1C8470R1C8470Q1532SK170Q1532SK170Q1572SC2240Q1572SC2240R195100R195100C15722pFC15722pFC15447pFC15447pFJ101RCAJ101RCA12R1A3470R1A3470R1A22.2megR1A22.2megR1A61KR1A61KC1701nFC1701nFR19347KR19347K+-IC104ATL082CP+-IC104ATL082C

48、P321R1C91KR1C91KCWRV1015KACWRV1015KA13245CWRV103500CWRV103500132R168100KR168100KC168100nFC168100nFR190220KR190220KQ161MPSA92Q161MPSA92Q1562SC2240Q1562SC2240Q1912SC4793Q1912SC4793R18910KR18910KR1A92.2megR1A92.2megR170470KR170470KR1976.8KR1976.8KR1C31KR1C31KR1C61.8KR1C61.8KR191220KR191220KC150180pFC15

49、0180pFC15215pFC15215pFQ1502SK170Q1502SK170C1G1100nFC1G1100nFC1601nFC1601nFD183BAV21D183BAV21+C1611uF+C1611uFC15510pFC15510pFD1824.7VD1824.7VC15122pFC15122pFR1C01KR1C01KR1C182R1C182R198470KR198470KQ1522SA970Q1522SA970R1A582R1A582Q1542SC2240Q1542SC2240C153180pFC153180pFG1G1Ground Solder TapG1G1Ground

50、Solder Tap1Q1582SA970Q1582SA970Q1652SA970Q1652SA970R1940.05R1940.05Q1552SA970Q1552SA970+-IC104BTL082CP+-IC104BTL082CP56784R1A8976R1A8976R12133KR12133KD1851N4148D1851N4148D1871N5404D1871N5404Q1632SA1015Q1632SA1015+C1621uF+C1621uFR188220KR188220KD1886.8VD1886.8V+C158100uF+C158100uFC15610nFC15610nFR1A7