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NAD T 743 Service Manual

Other manuals for T 743: Owner's Manual

Summary of T 743

  • Page 1

    Nad service manual t 74 3 t 743 a/v receiver a/v receiver draft date: 12 mar 2004.

  • Page 2: Safety Information

    2 safety information.

  • 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 part number description f751*ah 33-0101001-00-48 fuse 7a 250v time-lag5 x 20mm sic ul/csa f751*c 33-0141002-00-48 fuse 4a 250v time...

  • 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) 150 ± 20 mv s/n ratio (a-wtd, 1khz, 1 w, 8 ohm, sl/sr/bl) ≥≥≥≥≥ - 72 d...

  • Page 5

    5 dts section output level (vol 0 db) : fl/fr/c/sl/sr track 6 1 khz 0.9 ± 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 subwoofer outp...

  • Page 6

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

  • 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 indica...

  • Page 8: Wiring Diagram

    8 m ain b o ard s peaker b o ar d trigger board s econdary board s -vide o b o ard au di o b o ard co mp o nent vide o b o ard d igital b o ard v ide o b o ard po wer su pply bo ard #1 mu lti- c hannel pre- ou t b o ar d amp. Board #2 a mp . B o ard #1 tu ner j7 05 b t743 wire diagram date : 10 /03 ...

  • Page 9: Block Diagram

    9 block diagram.

  • Page 10: Special Function

    10 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 t89c51rd2 (u...

  • Page 11: Amplifier Adjustment

    11 r522 r545 r571 p501 p801 p802 r835 r836 p502 p503 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 ...

  • Page 12: Pcb Layout

    12 pcb layout audio board power supply (standby) / power switch.

  • Page 13

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

  • Page 14

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

  • Page 15

    15 dsp board - copper side dsp board - component side.

  • Page 16

    16 front / center amplifier board.

  • Page 17

    17 surround amplifier board.

  • Page 18

    18 keyboard - component side - copper side.

  • Page 19

    19 main board.

  • Page 20

    20 multi-channel board - component side - copper side.

  • Page 21

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

  • Page 22

    22 speaker terminal board trigger board video 6 board power supply (secondary) led board.

  • Page 23

    23 s-video board - component side s-video board - copper side.

  • Page 24: Schematic Diagram

    24 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 acit ors, unless other wise specified, are 50v , 10%..

  • Page 25

    25 component 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 26

    26 e c b 2sa2878 e c b 2sa933 dtc123esa e c b 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 27

    27 power supply (secondary) note: 1 . Resistors, unless otherwise specified, are 1/6w, 5%. 2. Components marked “ ” are safety critial p arts..

  • Page 28

    28 power supply (stand by) e c b 2sc1815 resistors : f-fusible, unless otherwise specified are carbon film. Note: 1 . Resistors, unless otherwise specified, are 1/6w, 5%. 2. Components marked “ ” are safety critial p arts..

  • Page 29

    29 dtc123esa e c b trigger 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 30

    30 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 31

    31 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 cap acit ors, unless other wise specified, are 50v , 10%..

  • Page 32

    32 e c b 2sa1016 2sc2362 b c e 2sa1606 2sc4159 b c e 2sa2031 2sc5669 e c b 2sb772 e c b 2sd600 dtc123esa e c b front / center amplifier note: 1. Resistors, unless other wise specified, are 1/6w , 5%. 2. All ceramic cap acit ors, unless other wise specified, are 50v , 10%. 3. Components marked “ ” ar...

  • Page 33

    33 surround amplifier e c b 2sc2362 b c e 2sa1606 2sc4159 b c e 2sa2031 2sc5669 e c b 2sd600k 2sd631k dtc123esa e c b e c b 2sa1016k 2sc2362 resist ors : rn-ceramic case, mo-met a l oxide, unless other wise specified are carbon film. Note: 1 . Resistors, unless otherwise specified, are 1/6w, 5%. 2. ...

  • Page 34

    34 speaker a & b rs-232.

  • Page 35

    35 digital in & out.

  • Page 36

    36 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 37

    37 e c b rn1241 dta114esa e c b pre-out note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%..

  • Page 38

    38 e c b 2sc1815 dsp note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 10%..

  • Page 39

    39 e c b 2sc1815 e c b 2sc1015 keyboard note: 1. Resistors, unless otherwise specified, are 1/6w, 5%. 2. All ceramic capacitors, unless otherwise specified, are 50v, 5%..

  • Page 40

    40 e c b 2sc2878 e b c ss8050 ss8550 dta114esa dtc114esa e c b multi-ch 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: Ic Block Diagram

    41 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 42

    42 tcm810 keyboard: u214 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 vcc reset**(reset) gnd tcm809 xenb tcm810 xenb 1 2 3 *3-p in sot-23b note: *3-pin sot-23b is equivalent to jedec to-...

  • Page 43

    43 hcf4094b keyboard: u204~u207 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 cl cl c...

  • Page 44

    44 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 45

    45 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 46

    46 m61516fp multi-channel board: u601.

  • Page 47

    47 21 18 28 45 53 5 45 13 45 27 48 35 45 45 66 65 33 42 50 19 20 45 43 47 45 43 24 23 29 45 54 49 42 17 45 42 44 36 60 61 63 45 52 41 56 57 51 7 44 11 34 42 62 45 58 44 1 59 55 45 45 45 64 45 30 25 16 14 31 45 12 45 8 44 26 6 9 15 22 4 32 38 2 3 39 37 10 40 exploded view.

  • Page 48: Exploded View Parts List

    48 exploded view parts list item part number description qty 1 10-0163017-01-00 plastic foot dome shape 4 2*ah,*c 10-0163045-72-00 linked goggle bezel (grey) 2 2*t 10-0163045-73-00 linked goggle bezel (titanium) 2 3*ah,*c 10-0163055-72-01 duo goggle bezel (grey) 2 3*t 10-0163055-73-01 duo goggle bez...

  • Page 49

    49 item part number description qty 37 13-0200502-22-00 self tap screw 2x5 type ìbî ni plt 8 38 13-0260500-02-00 self tap screw 2.6 x 5 p/h type ìaî ni plt 2 39 13-0260600-02-00 self tap screw 2.6 x 6 p/h type ìaî ni plt 6 40 13-0260803-02-00 self tap screw 2.6 x 8 b/h type ìaî ni plt 16 41 25-02100...

  • Page 50: Electrical  Parts List

    50 e reference no. Part no. Description power amp module 95-0907435-12-01 power amplifier module front left/right amp board pcb assembly 80-0907430-40-00 front left/right amp assembly capacitors c501,c513,c525 22-3476052-00-28 cap elec gr 4.7uf 50v 20% c503,c515,c527 22-4110203-10-28 cap mylar mcc-r...

  • Page 51

    51 reference no. Part no. Description q561,q564,q567 21-0100410-00-12 xtr ss pnp hfe 280-560 110mhz 2sa1016kg-aa resistors r522,r545,r571 30-0102106-01-64 vr semi-fix res cf 1k ohm b 30% r523,r547,r574 23-4228280-08-20 res rn 0.22 ohm 5% 5w sil 3 pin regulator u501 27-3001201-17-14 i.C. Volt reg 12v...

  • Page 52

    52 reference no. Part no. Description resistors r836,r835 30-0102106-01-64 vr semi-fix res cf 1k ohm b 30% r843,r844 23-4228280-08-20 res rn 0.22 ohm 5% 5w sil 3 pin dsp board pcb assembly 80-0907430-65-00 dsp assembly capacitors c1004,c1002 22-3106052-00-43 cap elec ss 1uf 50v 20% c1005 22-3226052-...

  • Page 53

    53 reference no. Part no. Description r1037,r1041,r1042,r1044,r1047, 44-0150120-51-00 res smd 1.5k ohm 5% 1/16w 0603 r1049,r1051,r1055,r1056,r1058, r1061,r1065,r1069,r1070,r1072, r1075,r1077 r1003-r1006,r1081 44-0330120-51-00 res smd 3.3k ohm 5% 1/16w 0603 r1082 44-0180120-51-00 res smd 1.8k ohm 5% ...

  • Page 54

    54 reference no. Part no. Description component video board pcb assembly 80-0907430-42-00 component video assembly capacitors c4310-c4312,c4325 22-3100022-00-43 cap elec ss 10uf 16v 20% c4316,c4318,c4320 22-3101022-00-43 cap elec ss 100uf 16v 20% c4313-c4315 22-3106052-00-43 cap elec ss 1uf 50v 20% ...

  • Page 55

    55 reference no. Part no. Description c242,c241 45-0102055-55-57 cap cer smd 1nf 50v 10% x7r 0603 c201,c202,c213,c215-c220,c222, 45-0104056-57-57 cap cer smd 0.1uf 50v 20% c229,c256 y5v 0603 c251-c254 45-0330055-55-57 cap cer smd 33pf 50v 10% x7r 0603 ir receiver d201 26-0941380-00-00 ir rx 940nm 37...

  • Page 56

    56 reference no. Part no. Description crystals x201,x202 28-5400200-06-33 crystal 40mhz 30ppm hc-49s led board pcb assembly 80-0907430-32-00 led assembly led d211 26-0012587-01-10 led red-green circular 5x807mm common anode tact switch s220 35-1001117-00-67 sw tact no 1p1t 50ma/12v ver h=7mm main bo...

  • Page 57

    57 reference no. Part no. Description capacitors c607,c611,c612 22-3220022-00-43 cap elec gs 22uf 16v 20% 85c c626 22-3221022-00-43 cap elec ss 220uf 16v 20% 85c c627,c628,c633,c634 22-3101022-00-43 cap elec ss 100uf 16v 20% 85c c677,c678,c689,c690 22-3470022-00-43 cap elec ss 47uf 16v 20% 85c c755,...

  • Page 58

    58 reference no. Part no. Description c640,c645,c650,c655,c675 22-3220022-00-43 cap elec gs 22uf 16v 20% 85c c667,c670 22-8226052-00-28 cap elec 2.2uf 50v 20% non-polar c684,c685,c687,c688 22-3331022-00-28 cap elec gr 330uf 16v 20% 85c c679,c680,c691,c692 22-3470022-00-43 cap elec ss 47uf 16v 20% 85...

  • Page 59

    59 reference no. Part no. Description f752*ah 33-0111006-00-48 fuse 1.6a 250v time lag lbc 5x20mm tsd ul/csa/vde/semko f752*c 33-0151006-00-48 fuse 800ma 250v time lag lbc 5x20mm tsd ul/csa/vde/semko fh751-fh752 33-1000000-00-88 fuse clip 0.05mm fc-53-11 relay m751*ah 32-3112210-00-40 relay power dc...

  • Page 60

    60 reference no. Part no. Description speaker terminal m8101 34-3000021-00-80 speaker terminal 6p binding m5101,m5102 34-3000022-00-80 speaker terminal 4p binding s-video board pcb assembly 80-0907430-26-00 s-video assembly capacitors c4101-c4107,c4115,c4158 22-3101022-00-43 cap elec ss 100uf 16v 20...

  • Page 61

    61 reference no. Part no. Description crystal x4101 28-5143200-06-19 crystal 14.318mhz 30ppm x4102 28-5177200-06-19 crystal 17.73447mhz 30ppm trigger board pcb assembly 80-0907430-68-00 trigger assembly diodes d351-d353 20-3251902-00-01 diode zener bzx55 5.1v 1/2w 5% d354,d355,d357,d359-d361 20-0000...

  • Page 62

    62 reference no. Part no. Description note: the components identified by mark are critical for risk of fire and electrical shock. Replace only with part number specified. : usa, canadian model only. : european model only. Resistors: mo-metal oxide, rn-ceramic case, mf-metal film. C4219,c4220 22-1102...

  • Page 63: Packing Diagram & Parts List

    63 packing diagram & parts list 6 5 4 1 2 3 5 9 7 8 item part no. Description qty. 1 64-0200001-01-00 polybag manual 1 2 31-6407520-00-98 fm wire antenna 1 31-6472801-00-28 am loop antenna w/stand 1 34-0081004-00-67 300 to 75 ohm adapter 1 61-0743004-42-99 owner's manual t743 gb/f/d/nl 1 61-0743004-...

  • Page 64: Version History

    64 version history serial no sofetware ver. Pcb assembly version r3xt74300186-r3xt74300200 v1.26 only power amp board issue 3, all other issue 4. R3xt74300001-r3xt74300185, v1.27 only power amp board issue 3, r3xt74300201-r3xt74300500 all other issue 4. R3xt74301035-r3xt74301234 v1.27 all are issue ...

  • Page 65: Ser

    65 ser vice manual t 74 3 a/v receiver nad electronics ltd london.