1. DL manuals
  2. NAD
  3. Stereo Receiver
  4. T 754
  5. Service Manual

NAD T 754 Service Manual

Other manuals for T 754: Owner's Manual
Manual is about: Surround Sound Receiver

Summary of T 754

  • Page 1

    Nad service manual t 754 t 754 surround sound receiver surround sound receiver draft date: 08 may 2007.

  • Page 2: Safety Information

    2 safety information ah version c version.

  • Page 3: Service Safety Precautions

    3 service safety precautions 1. Replacing the fuses caution: for continued protection against the risk of fire replace only with same type of fuse. Reference designator database part number description f751*ah 20-001-0078-90 fuse time-lag 10a/250vac 5x20mm ul/csa 5t f751*c,ct 20-001-0069-90 fuse 800...

  • Page 4: Specifications

    4 specifications power amplifier section rated distortion (rated power level into 8 ohms, thd 20 hz-20 khz fl/c/fr) ≤ 0.1 % (rated power level into 8 ohms, thd 20 hz-20 khz sl/sr/bs) ≤ 0.1 % input sensitivity (ref. 8 ohms, 1 khz) 296 ±±±±± 20 mv s/n ratio (a-wtd, 1khz, 1 w, 8 ohm, sl/sr/bl) ≥≥≥≥≥ - ...

  • Page 5

    5 dts section output level (vol 0 db) : fl/fr/c/sl/sr track 6 1 khz 0.3 ±±±±± 1.3 w channel difference (fl ref) : fl/fr/c/sl/sr track 6 1 khz ±±±±± 1.0 db harmonic distortion (audio filter) : fl/fr/c/sl/sr track 10-14 1 khz ≤≤≤≤≤ 0.08 % frequency response (20 hz to 20 khz) track 26-30 +2/-1.5 subwoo...

  • Page 6

    6 front panel rear panel / front panel view rear panel 1. Fm & am antenna 2. Soft clipping on/off 3. Monitor out 4. Cd input 5. Ir input & output 6. +12v trigger input & output 7. Component video in & component video out 8. Digital audio input & digital audio output 9. Power switch 10. Switched ac o...

  • Page 7: Disassembly Instructions

    7 disassembly instructions 1. Remove machine screws m4.0 x 8.0 ( 1 to 6 ) from the side panels. Remove tapping screw 3.0 x 8.0 ( 7 to 10 ) from the back panel. Refer to figure no. 1 . 2. Pull both sides of the top cover slightly outwards 11 and tilt approx. 35 ° and then remove in the direction as i...

  • Page 8: Wiring Diagram

    8 wiring diagram keyboard main board trigger board power switch board j8101b j713a j714a j715a j719a j720a j717a j710a j711a j712a j707a j704a j502b j709a j713b j714b j203a j204b j901b j753b video 6 input board j758b j757b j709b dsp board j604b j715b j1009b j1010b led board psu board component video...

  • Page 9: Wiring Diagram Parts List

    9 wiring diagram parts list item database part number description remark 1 17-012-2986-90 cable assy 2 ways awg=26 2.5p ul2468 l=440mm amp1 bd-j511a 2 17-012-2987-90 cable assy 4 ways awg=18 3.96p ul1007 l=420mm amp1 bd-j581a 3 17-012-2988-90 cable assy 6 ways awg=26 2.5p ul1007 l=320mm amp1 bd-j503...

  • Page 10

    10 item database part number description remark 24 17-012-2999-90 cable assy 6 ways awg=26 2.5p ul 1533x1c l=540mm po bd-j611a 25 17-012-2948-90 cable assy 1 way awg=16 ul1672 brown l=100mm ps bd-j757 26 17-012-2874-90 cable assy 1 way awg=16 ul1672 blue l=100mm ps bd-j756 27 17-012-2965-90 cable as...

  • Page 11: Block Diagram

    11 block diagram selector in audio in/out trigger hcf4094 matrix cd tuner key ir in volume encode v4 v6 v5 v1 v2 v3 in ex sub v3 out v4 out in in in ex surr ex cen ex bsurr 24c16 eeprom rst ic tcm810 mute mute out ms audio amp power mute mute mute mute amp power pre-out spk relay relay out spk out s...

  • Page 12: Special Function

    12 special function feature keys press on front panel reset for ah version video 6 +source up reset for c version video 6 + source down ntsc / pal selection video + memory vfd all display audio 6 + tone defeat am freq. Step am/fm + fm mute details & waveforms on system test & debugging m6759(u202) m...

  • Page 13: Amplifier Adjustment

    13 amplifier adjustment idle current 1. Rotate r522 fully clockwise. 2. Connect dc millivoltmeter to p501 (i.E. Across half of r523, 0.22 ohm resistor). 3. Turn on the unit. 4. Adjust r522 for 1mv reading on voltmeter. 5. Leave power on for at least 5 min, and check for idle current again. 6. Repeat...

  • Page 14: Pcb Layout

    14 pcb layout audio board power supply (standby) board.

  • Page 15

    15 component video board - component side component video board - copper side digital board - component side side digital board - copper side.

  • Page 16

    16 dsp board - copper side dsp board - component side.

  • Page 17

    17 front / center amplifier board - component side.

  • Page 18

    18 front / center amplifier board - copper side.

  • Page 19

    19 surround amplifier board - component side.

  • Page 20

    20 surround amplifier board - copper side.

  • Page 21

    21 key board/power switch - component side key board/power switch - copper side.

  • Page 22

    22 main board.

  • Page 23

    23 multi-channel board - component side.

  • Page 24

    24 multi-channel board - copper side.

  • Page 25

    25 pre-out board - copper side pre-out board - component side.

  • Page 26

    26 speaker terminal board power switch / trigger board video 6 board.

  • Page 27

    27 secondary / isc board - component side secondary / isc board - copper side.

  • Page 28

    28 s-video board.

  • Page 29

    29 composite video board - component side composite video board - copper side.

  • Page 30: Schematic Diagram

    30 schematic diagram audio switch resistors : unless otherwise specified are carbon film. Note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic cap acitors, unless other wise specified, are 50v , 10%..

  • Page 31

    31 component video resistors : unless otherwise specified are carbon film. Note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic cap acitors, unless other wise specified, are 50v , 10%..

  • Page 32

    32 composite video resistors : unless otherwise specified are carbon film. Note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic cap acit ors, unless other wise specified, are 50v , 10%..

  • Page 33

    33 e c b 2sa1015 2sc1815 e c b 2sa1016 power supply (secondary) note: 1 . Resistors, unless otherwise specified, are 1/6w, 5%. 2. Components marked are safety critial p arts..

  • Page 34

    34 power supply (stand by) resistors : f-fusible, unless otherwise specified are carbon film. Note: 1 . R e s is t o r s , u n l e s s o therwise specified, are 1/6w, 5%. 2. Components marked are safety critial p arts..

  • Page 35

    35 trigger resistors : unless otherwise specified are carbon film. Note: 1 . R e s is t o r s , u n l e s s o therwise specified, are 1/6w, 5%. 2. All ceramic cap acit ors, unless other wise specified, are 50v , 10%..

  • Page 36

    36 video 6 resistors : unless otherwise specified are carbon film. Note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic cap acit ors, unless other wise specified, are 50v , 10%..

  • Page 37

    37 speaker a & b.

  • Page 38

    38 preout note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%..

  • Page 39

    39 digital input / output note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic cap acit ors, unless other wise specified, are 50v , 10%..

  • Page 40

    40 e c b 2sa933 e c b 2sc1740 e c b 2sc1815 2sc2878 dtc144esa dtc123esa e c b s-video resistors : unless otherwise specified are carbon film. Note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%..

  • Page 41

    41 e c b 2sa1016 2sc2362 b c e 2sa1606 2sc4159 b c e 2sa2031 2sc5669 e c b 2sd600k 2sd631k dtc123esa e c b front / center channel power amplifier note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%. 3. Components marked ar...

  • Page 42

    42 e c b 2sc2362 e c b 2sa1015 2sa1815 b c e 2sa1606 2sc4159 b c e 2sa2031 2sc5669 e c b 2sd600k 2sd631k dtc123esa e c b e c b 2sa1016k 2sc2362 e c b 2sc1740s e c b 2sb772 surround channel power amplifier resistors : rn-ceramic case, mo-metal oxide, unless otherwise specified are carbon film. Note: ...

  • Page 43: Dsp

    Note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%. 43 dsp.

  • Page 44

    44 keyboard note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 5%..

  • Page 45

    45 e c b 2sc2878 e b c ss8050 ss8550 dtc144esa dta144esa e c b multi-channel resistors : unless otherwise specified are carbon film. Note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%..

  • Page 46

    46 e b c 2sd600k main board note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%..

  • Page 47: Ic Block Diagram

    47 1 2 3 4 5 6 7 8 9 10 dir a1 a2 a3 a4 a5 a6 a7 a8 gnd 20 19 18 17 16 15 14 13 12 11 vcc g b1 b2 b3 b4 b5 b6 b7 b8 (1) (2) (3) (4) (5) (6) (7) (8) (9) (11) (19) (18) (17) (16) (15) (14) (13) (12) oe ck d0 1d c1 en d1 d2 d3 d4 d5 d6 d7 q0 q1 q2 q3 q4 q5 q6 q7 74lvq574 dsp board: u1008, u1009 w27c020...

  • Page 48

    48 data 7:0, emad 7:0, gpio 7:0 cs parallel or serial host interface cmpclk, sclkn2 compressed data input interface pll clock manager va framer shifter input buffer controller dd dc mclk sclk lrclk audata[2.0] xmt958/audata3 cmpdat, sdatan2 cmpreq lrclkn2 sclkn1 stcclk2 lrclkn1 sdatan1 digital audio...

  • Page 49

    49 at24c16 keyboard: u210 sda vss scl wc vcc / e2 m24cxx 1 2 3 4 8 7 6 5 / e2 / e2 / e2 nc / e1 / e1 / e1 / nc nc / e0 / e0 / nc / nc nc /1kb /2kb /4kb /8kb 16kb 74hcu04 digital board: u1201 & u1202 1a 1y 2a 2y 3a 3y gnd 1 2 3 4 5 6 7 14 13 12 11 10 9 8 6a v cc 6y 5a 5y 4a 4y 74hc251 digital board: ...

  • Page 50

    50 hcf4094b keyboard: u204~u207 & u211 serial in clock strobe latch 1 3-state 1 output enable 2 serial out q' s 10 serial out q s 9 15 1 d q cl cl 3 cl cl 1 cl cl 2 d q cl cl latch 2 tr tr latch 3 tr tr 3- state 2 3- state 3 3 d q cl cl q stages 3 - 7 2 2 2 2 2 2 2 2 q3 q2 q1 vss vdd q7 q8 q6 q5 q4 ...

  • Page 51: Com Out/in

    51 m6759 keyboard: u201 & u202 data bus data bus port 0 drivers p0.7:0 port 2 drivers p2.7:0 data bus data bus program address register program counter buffer dptr incrementer port 1 drivers p1.7:0 port 3 drivers p3.7:0 port latch port latch port latch serial port timer interrupt logic acc alu reg1 ...

  • Page 52: Com "y" Out/in

    52 0 2 com "y" out/in 3 1 inh v ee gnd 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 v cc 2 1 com "x" out/in 0 3 a b y channels in/out x channels in/out x channels in/out y channels in/out 74hc4052 ba7660fs component video board: u4301 mute ina gnd inb gnd n.C. Inc gnd 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 ...

  • Page 53

    53 lc74763 s-video board: u4101.

  • Page 54

    54 m61516fp multi-channel board: u6101 & u6102.

  • Page 55

    55 1 2 3 19 5 6 7 8 10 12 13 14 15 16 9 11 17 18 4 20 20 20 21 20 22 22 22 23 24 25 25 25 25 26 27 27 27 28 29 30 31 31 32 35 36 37 38 39 40 41 42 43 62 44 45 46 48 49 50 51 52 53 54 55 47 57 58 59 60 61 78 65 67 39 56 87 86 68 69 70 71 72 73 74 75 76 77 64 79 80 81 82 83 84 66 85 63 39 43 34 33 25 ...

  • Page 56: Exploded View Parts List

    56 exploded view parts list item database part no. Description qty 1 08-002-0065-90 fan dc 60x10mm 12v 0.09a 3000rpm df126010sl l=450mm w/ 2.5p connector 2 2 08-002-0066-90 fan dc 60x10mm 12v 0.09a 3000rpm df126010sl l=350mm w/ 2.5p connector 2 3 10-005-0188-90 transformer pw ei-114 115v/230v t754 t...

  • Page 57

    57 item database part no. Description qty 39 22-006-0081-00 washer steel i/d 3.5 x o/d 8.0 0.4mm thk. Zinc plt. 22 40 22-005-0034-00 washer spring i/d 4 x 0/d 7 x 1 thk 2 41 22-008-0025-00 outer tooth washer id 4.2 x od 8.2 x 0.4 thk nickel plt 1 42 22-005-0036-90 washer spring i/d 5.2 x o/d 8 x 1.2...

  • Page 58

    58 item database part no. Description qty 21-002-0149-92 input button lozenge t752 (new titanium) r.1 [for titanium ver.] 1 73 21-002-0150-92 input button (graphite) r.5 [for grey ver.] 3 21-002-0151-92 input button (new titanium) r.5 [for titanium ver.] 3 74 25-024-0309-92 duo button (graphite) r.2...

  • Page 59: Electrical Parts List

    59 electrical parts list reference no. Database part no. Description power amp module pcb assembly 50-940-0754-90 t754 power amp module front & center amp board pcb assembly 27-909-0754-90 t754ah front and center amp board assembly resistors r574,r547,r523 02-005-0072-00 res rn 0.22 ohm 5% 5w sil st...

  • Page 60

    60 reference no. Database part no. Description surround amp board pcb assembly 27-910-0754-90 t754ah surround amp board assembly regulators u872 01-004-0048-00 ic volt reg 5v 1a to-220 njm7805fa isowatt u871 01-004-0049-00 ic volt reg 12v 1a to-220 njm7812 isowatt resistors r844,r843,r8103 02-005-00...

  • Page 61

    61 reference no. Database part no. Description r823-824, r827-828, r899, r8102, r8114-8119 17-016-0080-90 jumper wire dia. 0.5mm for l smaller than 14mm roll diodes d801-d809,d814-d818,d820- d825,d871-d874,d880-d883 04-001-0001-00 diode sw 4ns do35 1n4148 main board pcb assembly 27-901-0754-90 t754a...

  • Page 62

    62 reference no. Database part no. Description diodes d751-d756 04-001-0003-00 diode rect 1a/1000v do41 win4007 transistors q751 05-001-0072-00 xtr ss npn hef 100 200mhz to-92 c1815y relay m751 07-005-0042-90 relay miniature 2p1t sdt-s-112dmr standby transformer t751 10-005-0186-90 transformer pw ei...

  • Page 63

    63 reference no. Database part no. Description c208,c209,c210,c211,c259 03-002-0143-00 cap elec ss 47uf 16v 20% 85c rad height = 7mm c224 03-002-0146-00 cap elec gr 4700uf 25v 20% 85c rad ir d201 04-004-0008-91 ir rx 940nm 37.9khz shield st pic-37143te5-h transistors q204,q203 05-001-0072-00 xtr ss ...

  • Page 64

    64 reference no. Database part no. Description r265,r267 02-007-0298-00 res smd 680 ohm 5% 1/16w 0603 r252,r251 02-007-0299-00 res smd 10m ohm +/-5% 1/16w 0603 smd capacitors c201-c202,c213,c215- c222,c229,c256,c257 03-009-0075-00 cap cer smd 0.1uf 50v 20% y5v 0603 c241,c242 03-009-0112-00 cap cer s...

  • Page 65

    65 reference no. Database part no. Description smd resistors r1151 02-007-0042-00 res smd 1k ohm 5% 1/16w 0603 l1011 02-007-0089-00 res smd 0 ohm +/-5% 1/10w 0805 r1090,r1091 02-007-0135-00 res smd 2.7k ohm 5% 1/16w 0603 r1092,r1093 02-007-0141-00 res smd 100 ohm 5% 1/16w 0603 r1008,r1020- r1021,r11...

  • Page 66

    66 reference no. Database part no. Description audio board pcb assembly 27-919-0754-90 t754ah audio board assembly capacitors c3101-c3113,c3115 03-002-0073-00 cap elec gs 22uf 16v 20% 85c rad height = 7mm jacks m303 15-003-0027-90 rca jack 4 r-r/w-w pcb mount gold m301,m302 15-003-0029-90 rca jack 6...

  • Page 67

    67 reference no. Database part no. Description smd capacitors c1232, c1233, c1234, c1235 03-009-0114-00 cap cer smd 220pf 50v 10% x7r 0603 multi-channel board pcb assembly 27-923-0754-90 t754ah multi-channel board assembly capacitors c607,c6201-c6216 03-002-0073-00 cap elec gs 22uf 16v 20% 85c rad h...

  • Page 68

    68 reference no. Database part no. Description c621,c622,c637,c642,c667, c679,c680,c691,c692 03-002-0143-00 cap elec ss 47uf 16v 20% 85c rad height = 7mm max c626 03-002-0150-00 cap elec ss 220uf 16v 20% 85c 8x9mm rad diodes 03-002-0150-00 cap elec ss 220uf 16v 20% 85c 8x9mm rad d601 04-001-0001-00 ...

  • Page 69

    69 reference no. Database part no. Description power switch board pcb assembly 27-925-0754-90 t754ah power switch board assembly capacitors c764 03-007-0014-00 hc cer cap 0.01uf/250vac ±20% y5v rad jy16f103mk02 ul/csa/vde capacitors 11-001-0061-90 power switch tv-8 10a/250vac ul/csa/vde/f/d/s ps3-22...

  • Page 70

    70 reference no. Database part no. Description c4134,c4149,c4101-c4107, c4109-c4111,c4113-c4115, c4158 03-002-0132-00 cap elec ss 100uf 10v 20% 85c rad height = 7mm max c4116 03-002-0135-00 cap elec gs 1000uf 10v 20% 85c rad st5 c4141,c4133,c4137 03-002-0137-00 cap elec ss 1uf 50v 20% 85c rad height...

  • Page 71

    71 reference no. Database part no. Description u352 01-004-0050-00 ic volt reg 12v 0.1a to-92 lm78l12 resistors r358,r359 02-010-0012-00 res mo 150 ohm 5% 2w axial diodes d354-d359,d361,d3501 04-001-0003-00 diode rect 1a/1000v do41 win4007 reel transistor q351 05-001-0076-00 xtr ss npn hfe20 250mhz ...

  • Page 72

    72 reference no. Database part no. Description smd resistors j4301-j4303 02-007-0089-00 res smd 0 ohm +/-5% 1/10w 0805 isc board pcb assembly 27-934-0754-90 t754ah isc board assembly resistors r793,r790 02-005-0062-00 res rn 0.22 ohm 5% 5w sil 3 pin command pin2 ww r837-r841 02-010-0011-00 res mo 0....

  • Page 73

    73 packing diagram & parts list 9 8 7 6 1 2 3 4 5 item database part no. Description qty 1 24-003-0127-90 polyb ag manual 260 x 350 x 0.03mm w/s ilk s c r e e n r e c yc le r .0 1 2 25-027-0001-90 fm wir e ante nna l=2700mm tr ans par e nc e w/y-te r minals (r ohs ) 1 25-027-0002-90 ante nna am loop...