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NAD T741 Service Manual

Other manuals for T741: Owner's Manual

Summary of T741

  • Page 1

    Nad t 741 s u r r o u n d sound receiver t 741 surround sound receiver ser vice manual.

  • Page 2: Service Safety Precautions

    2 service safety precautions 1. Replacing the fuses caution: for continued protection against the risk of fire replace only with same type of fuse. Reference no part number description m271 *c 5120-0024-0 3.15a time-lag 5x20 vde-semko note: : usa, canadian model only. : european model only. 2. Safet...

  • Page 3: Specifications

    3 specifications power amplifier and preamplifier section (all channels stated 8 ohms) rated distortion (thd 20hz-20 khz fl/c/fr) ) 0.08% (thd 20hz-20 khz sl/sr) ) 0.3% input sensitivity (ref. 8 ohms, 1 khz) 180+/-30 mv s/n ratio (a-wtd, 1khz, 1w, 8 ohm) * -78 db (a-wtd, 1khz, 80w, 8 ohm) fl/fr/c * ...

  • Page 4

    4 am tuner section input level is expressed as the reading in open-circuit of 75-ohm source impedance signal generator usable sensitivity (999/1000khz) ) 30 dbµ s/n ratio (5mv in) * 38 db thd (5mv in) ) 3% if rejection (450 khz) * 36 db image rejection (f+2xif) * 28 db selectivity * 17 db output 130...

  • Page 5: Rear Panel / Front Panel

    5 1 2 3 4 5 6 7 8 9 10 11 12 1. Fm & am antenna 2. Tape 1 & cd inputs 3. 5.1 channel input 4. Video 1 - video 4 (audio & video) 5. Nad-link input / output 6. Digital audio inputs / outputs 7. 12v trigger input 8. Audio pre outs 9. Monitor out 10. Soft clipping 11. Speakers: front, center & surround ...

  • Page 6: Disassembly Instructions

    6 disassembly instructions 1. Remove machine screws m 4.0 x 6.0 ( 1 to 6 ) from the side panels. Remove tapping screw 3.0 x 8.5 ( 7 )from the back panel. Refer to figure no.1. Figure no.1 2. Pull both sides of the top cover slightly outwards 8 and tilt approx. 35˚ and then remove in the direction as...

  • Page 7

    8 7 p702 p701 power switch pcb j401a ac3 pcb j203b j101a j604b j601b j208a j208b j203a j206a j207a j207b secondary pcb j701a j202b j206a jp210 jp211 j702b jp210 j602b t201a t202a jp207 jp206 m704b c230 jp209 jp203 j206b jp204 jp205 c221 p261 p260 p262 j101b j201b p264 psu pcb p266 p265 digital pcb p...

  • Page 8

    9 10 osc rf vt block diagram coaxial x2 optical x1 74hc153 4053 74ls157 m62446fp s-v ideo selector cd4052 tempera t ure protection tuner l tuner r power down detect pin. For spk of f, mute on, vfd of f. Spk. A and b fl t rigger out fl out2 out3 out1 out4 fr center sl sr sub fr center sl sr sub v ide...

  • Page 9

    11.

  • Page 10: Alignment Procedures

    12 alignment procedures amplifier section idle current step item connection adjustment adjust for 1 front left channel voltmeter to m714 on main board vr7703 1mv±0.2mv 2 front right channel voltmeter to m713 on main board vr7702 1mv±0.2mv 3 center channel voltmeter to m712 on main board vr7701 1mv±0...

  • Page 11: Important Notes

    13 fm/rds section - fm mono: 1khz, 75khz devi., 60db/μv - fm stereo: 1khz, 67.5khz devi., 60db/μv pilot signal 19khz 7.5khz devi. Outputs - connect the non-inductive type resistor of 8 ohms to the all speaker terminals unless otherwise noted. Item fm if/rf stereo distortion stereo separation muting ...

  • Page 12: Pcb Layout

    14 pcb layout s-video board video-5 board volume board.

  • Page 13

    15 video board tuner board.

  • Page 14

    16 surround amplifier board primary board secondary board.

  • Page 15

    17 audio board psu board.

  • Page 16

    18 multi-channel board - component side.

  • Page 17

    19 multi-channel board - solder side.

  • Page 18

    20 main board.

  • Page 19

    22 21 ac3 board - component side ac3 board - solder side.

  • Page 20

    23 24 key board digital board speaker board led board power switch board.

  • Page 21

    26 25 schematic diagram ac3 / dts note: 1. Resistors, are carbon film 5% 1/10w unless otherwise specified. 2. Ceramic capacitors, are 50v 10%. Unless otherwise specified..

  • Page 22

    27 28 main note: 1. Resistors, are carbon film 5% 1/8w unless otherwise specified. Mf-metal film 2. Ceramic capacitors, are 50v 10%. Unless otherwise specified..

  • Page 23

    30 29 ( from ac3 j601b ) out1 out2 out3 out4 avdd swin gnds srin slin gndc cin gndr rin gndl byr byl dvdd clk data latch dgnd agnd swout srout slout cout rout lout avss1 avss2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 lin u60...

  • Page 24

    31 32 keyboard note: 1. Resistors, are carbon film 5% 1/8w unless otherwise specified. 2. Ceramic capacitors, are 50v 10%. Unless otherwise specified..

  • Page 25

    34 33 tuner note: 1. Resistors, are carbon film 5% 1/8w unless otherwise specified. 2. Ceramic capacitors, are 50v 10%. Unless otherwise specified..

  • Page 26

    35 36 3 4 5 2 1 m501 s_v2 in 3 4 5 2 1 m502 s_v1 in 3 4 5 2 1 m503 s_v3 in 3 4 5 2 1 m504 s_v3 out 3 4 5 2 1 m505 mon out 5 4 3 2 1 6 7 8 9 10 j715b 10pin 5 4 3 2 1 6 7 8 9 10 j716b 10pin c501 47u/10v c502 47u/10v c503 47u/10v c504 47u/10v c505 47u/10v c506 47u/10v c507 470u/10v c508 470u/10v c509 2...

  • Page 27

    38 37 q7701 a56 q7707 a06 c7701 10u/50v q7713 2sc1845 q7714 2sc1845 r7701 10k r7711 680r r7714 470r r7720 10r r7723 6k2 c7711 100p c7712 100p c7717 220u/50v r7726 5k1 z7701 10v r7729 33k d7701 1n4148 d7702 1n4148 r7737 120r r7740 2k2 r7743 1k8 vr7701 1k q7724 a13 c7720 47p q7708 a06 q7727 2sc5197 q7...

  • Page 28

    39 40 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 u302 tc9273 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 u301 4053 video3 out video4 out video2 in video1 in video3 in video4 in fr gnd fl +12v -12v v5_r cd_r t_r t_i_r t_o_r v5_l cd_l t_l t_i_l t_o_l t_mon dgnd latch data cl...

  • Page 29

    41 q203 a56 q204 a06 c201 10u/50v q201 2sc1845 q202 2sc1845 r201 10k r202 680r r205 470r r206 10r r204 6k2 c202 100p c203 100p c205 220u/50v r203 5k1 z201 10v r245 33k d201 in4148 d202 in4148 r209 120r r208 2k2 r207 1k8 vr201 1k q205 a13 c204 47p q207 a06 q208 2sc5198 q206 a56 q209 2sa1941 c206 10u/...

  • Page 30

    42 psu note: 1. Resist ors are carbon film 5% 1/8w unless other wise specified. Mf - met al film 2. Ceramic cap acit ors are 50v 10%. Unless other wise specified. 3. Components marked “ ” are safety critical p a r ts..

  • Page 31: Ic Block Diagram

    43 ic block diagram ac3 board u101: 74hc153 14 7 9 a 2 1 6 5 4 3 15 b 1g 1c0 tg tg tg tg tg tg tg tg tg tg tg tg 1c1 1c2 1y 2y 1c3 10 11 12 13 2c0 2c1 2c2 2c3 2g 1 1g vcc 16 2 b 2g 15 3 1c3 a 14 4 1c2 2c3 13 5 1c1 2c2 12 6 1c0 2c1 11 7 1y 2c0 10 8 gnd 2y 9 ac3 board u102: 74hc157 4 1y 7 2y 9 3y 12 4...

  • Page 32

    V cc (32) oe, ce and program logic data outputs o0-o7 (13-15, 17-21) output buffers y-gating cell matrix identification y decoder x decoder oe(24) ce(22) pgm(31) a0-a17 address inputs (2-12, 25-30) gnd(16) vpp(1) 44 amplifier 1 output inverting input non-inverting input v – amplifier 2 v + output in...

  • Page 33

    45 rxp rs422 receiver clock & data recovery de-mux audio serial port registers mux mux vd+ dgnd va+ va+ filt agnd mck m3 m3 m2 m1 m0 sdata sck fsync c u verf cs12/fck sel c0/e0 ca/e1 cb/e2 cc/f0 cd/f1 ce/f2 ref cbl rxn 9 10 13 16 6 5 4 3 2 27 25 15 28 14 1 11 12 26 23 24 18 17 19 21 20 22 8 7 ac3 bo...

  • Page 34

    46 1 1a 14 vac 2 1y 13 6a 3 2a 12 6y 4 2y 11 5a 5 3a 10 5y 6 3y 9 4a 7 gnd 8 4y ac3 board u114: 74hcu04 1 y 1b 2 y 0b 3 y 1c 4 z c 5 z 0c 6 e 7 v ee 16 v dd 15 z b 14 z a 13 y 1a 12 y 0a 11 s a 10 s b 8 v ss 9 s c e s c s b s a level converter y 0c y 1c z c y 0b y 1b z b y 0a y 1a z a audio board u3...

  • Page 35

    47 2 s1 1 v ss 26 v dd 27 s1 3 s2 26 s2 4 s3 25 s3 5 s4 24 s4 6 s5 23 s5 7 s6 22 s6 8 s7 21 s7 9 s8 20 s8 10 s9 19 s9 11 s10 18 s10 12 s11 13 gnd 14 ck 15 data 16 resister 17 s11 (l-ch) 10bit latch circuit level shift + shift resister circuit (r-ch) 10bit latch circuit (same as l-ch circuit) audio b...

  • Page 36

    48 dout ack word address buffers start/stop logic control logic state counters slave address comparators a0 a1 a2 scl wp sda vss vcc xdec data in storage high voltage/ timing control e 2 prom column decoders sense amps shift registers vcc a0 8 1 wp a1 7 2 scl a2 6 3 sda vss 5 4 key board u202: eepro...

  • Page 37

    49 amplifier 1 output inverting input non-inverting input v – amplifier 2 v + output inverting input non-inverting input 1 2 3 4 8 7 6 5 + – – + multi-channel board u601, u602, u606, u607, u609: njm5532 u603, u608: njm4558d u701-u703: njm4558m 1 2 l-s1 vss shift register level shifter level shifter ...

  • Page 38

    50 tuner board u902: lc72723m vdda 3 reference voltage antialiasing filter data decoder vref 1 vref flout 5 cin 6 pll (57khz) clock recovery (1187.5hz) + _ vddd 11 vssd 10 rdda 14 rdcl 15 mode 12 rst 13 rds-id/ready 16 vssa 4 mpxin 2 test 7 test 57khz bpf (scf) smoothing filter osc clk(4.332mhz) 9 x...

  • Page 39

    51 s-video assembly u501: 4052 3 13 logic level conversion binary to 1 of 4 decoder with inhibit b 10 c 9 in h 6 v dd 16 v ss 8 v ee 7 tg tg tg tg common x out/in tg tg tg tg common y out/in 3 2 1 0 13 15 11 12 x channels in/out 1 5 2 4 0 1 2 3 y channels in/out a 11 v dd 16 7 4 6 2 5 5 4 1 3 12 2 1...

  • Page 40: Electrical Parts List

    52 ac3 board 1000 pcb-n0a00c-ac3 ac3 assembly miscellaneous 2702 2954-3008-0000 tapping 3x8mm b-tite 2703 4151-9931-0 insulation bushing 2704 2954-2606-0000 screws bt 2.6x6 capacitors c101 150f-104k-j-bd cc 50v 0.1μf 10% 0805 c102 150e-104m-j-bd cc 25v 0.1μf 20% 0805 c103 150f-104k-j-bd cc 50v 0.1μf...

  • Page 41

    53 c123 150f-562k-j-bd cc 50v 5600pf 10% 0805 c125 150e-104m-j-bd cc 25v 0.1f 20% 0805 c126 157d-227m-5-kw ce 16v 220μf 20% rl 6x12 c127 150e-104m-j-bd cc 25v 0.1f 20% 0805 c128 157d-106m-5-gm ce 16v 10μf 20% rl 4x7 c129 150e-104m-j-bd cc 25v 0.1f 20% 0805 c130 157e-105m-5-ei ce 25v 1μf 20% rl 3x5 c...

  • Page 42

    54 heatsinks h-u121 5400-0831-0 heatsink h-u123 5400-9130-0 heat sink for 7805 2438- wafers j101a 2102-101s-004 wafer 10p p2.5 st. J203b 2101-1581-0 flexible conn. 35p j601b 2102-121s-004 12p st.Wafer j604b 2102-031s-004 3 pin st. Wafer coils l101-l103 1801-100k-m coil 10μh 10% bl7.0 l104 1807-273j-...

  • Page 43

    55 r138 4720-103j-j rmg 1/10w 10k 5% 0805 r139 4720-102j-j rmg 1/10w 1k 5% 0805 r140 4720-101j-j rmg 1/10w 100r 5% 0805 r1401, r1404 4720-102j-j rmg 1/10w 1k 5% 0805 r1405 4720-104j-j rmg 1/10w 100k 5% 0805 r1406 4720-203j-j rmg 1/10w 20k 5% 0805 r150 4720-103j-j rmg 1/10w 10k 5% 0805 r155 4720-153j...

  • Page 44

    56 u125 3130-2020-3 ic 7805 reg 5v 1.5a u131 3130-0890-0 ic njm4558d dual op amp. U134 3130-9560-0 njm5532 ic 'dip8' surround amp board 2000 pcb-n0a00c-amp2 sl/sr power amp assembly capacitors c201 157f-106m-5-iue ce 50v 10μf 20% rl 5x11 c202, c203 150f-101k-2-fc cc 50v 100pf 10% at 3.5x c204 150f-4...

  • Page 45

    57 q214 4860-8890-0 tr mps a06 vce 80v ns q215 4860-8900-0 tr mps a13 vce 100v q216 4860-8890-0 tr mps a06 vce 80v ns q217 4860-8910-0 tr mps a56 vce 80v ns q218 4860-5210-5 tr 2sc5198-0 hfe 80-160 q219 4860-5220-5 tr 2sa1941-0 hfe 80-160 q220 4860-0190-5 tr 2sc 1845 (f.E) rl q221 485c-123j-5 tr dtc...

  • Page 46

    58 audio assembly 3000 pcb-n0a00c-aud audio assembly capacitors c301-c306 150f-101k-2-fc cc 50v 100pf 10% at 3.5x c309-c314 150f-101k-2-fc cc 50v 100pf 10% at 3.5x c315, c316 150f-103k-2-fc cc 50v 0.01μf 10% at 3.5 c317, c318 150f-223k-2-fd cc 50v 0.022μf 10% at c319-c324 157d-335m-5-ii ce 16v 3.3μf...

  • Page 47

    59 r762 4701-104j-c rcf 1/8w 100k 5% ats ic u761 3130-7370-0 ic 74hct00 nand gate key assembly 2200 pcb-n0a00c-key key assembly led display 2119 2460-1890-2 vfd 12-mt-84gnk futaba capacitors c205, c207 150f-104z-5-iu cc 50v 0.1μf +80/-20% rl c203, c204 150f-220k-5-gg cc 50v 22pf 10% rl 4x4 c201 157b...

  • Page 48

    60 q201 4860-0050-5 tr ss8050 c/d samsung rl resistors r201-r203 4701-681j-c rcf 1/8w 680r 5% ats r204-r206 4701-821j-c rcf 1/8w 820r 5% ats r207-r209 4701-182j-c rcf 1/8w 1.8k 5% ats r210-r212 4701-222j-c rcf 1/8w 2.2k 5% ats r213,r214 4701-472j-c rcf 1/8w 4.7k 5% ats r215-r218 4701-103j-c rcf 1/8w...

  • Page 49

    61 c7720-c7722 150f-470j-2-fc cc 50v 47pf 5% at 3.5x2 c7723-c7729 150f-223k-2-fd cc 50v 0.022μf 10% at c7730 157d-107m-5-iu ce 16v 100μf 20% rl 5x11 c7731-c7733 150f-104k-2-fc cc 50v 0.1μf 10% at c7739, c7740 157i-477m-5-x& ce 63v 470μf 20% rl c7741, c7742 157d-476m-5-im ce 16v 47μf 20% rl 5x7 c7743...

  • Page 50

    62 q7724-q7726 4860-8900-0 tr mps a13 vce 100v q7701-q7726 4860-8910-0 tr mps a56 vce 80v ns resistors r703, r705 4701-102j-c rcf 1/8w 1k 5% ats r704, r706 4701-104j-c rcf 1/8w 100k 5% ats r731 4701-102j-c rcf 1/8w 1k 5% ats r732 4701-333j-c rcf 1/8w 33k 5% ats r733, r724 4718-391j-2-x rmf 1w 390r 5...

  • Page 51

    63 c6103, c6104 150f-104k-2-fc cc 50v 0.1μf 10% at c611, c614, c615 157d-226m-5-ii ce 16v 22μf 20% rl 5x5 c612 150f-103k-2-fc cc 50v 0.01μf 10% at 3.5 c613 157d-227m-5-kw ce 16v 220μf 20% rl 6x12 c617, c618, c639 157d-335m-5-ii ce 16v 3.3μf 20% rl 5x5 c619-c622 157d-475m-5-iu ce 16v 4.7μf 20% rl 5x1...

  • Page 52

    64 r6016,r6109 4720-102j-j rmg 1/10w 1k 5% 0805 r6017,r6108 4720-223j-j rmg 1/10w 22k 5% 0805 r602,r604,r606 4701-104j-c rcf 1/8w 100k 5% ats r607,r609,r611 4701-331j-c rcf 1/8w 330r 5% ats r608,r610,r612 4701-104j-c rcf 1/8w 100k 5% ats r6100,r659,r660 4701-202j-c rcf 1/8w 2k 5% ats r6102-r6105 470...

  • Page 53

    65 psu assembly 7100 pcb-n0a01c-psu psu assemblyna00c capacitors c275 157e-227m-5-pu ce 25v 220μf 20% rl c276 150f-223k-2-fd cc 50v 0.022μf 10% at c277 150f-103k-2-fc cc 50v 0.01μf 10% at c278 8910-0091-0 cc 400v 0.01μf +-20% rl c503,c504 150f-102k-2-fc cc 50v 1000pf 10% at 3.5 diodes d261-d264 *ah ...

  • Page 54

    66 resistors r260 4717-2r2j-2 rmf 1/2w 2.2r 5% at r261-r263 4718-r22j-2 rmf 1w 0.22r 5% at speaker assembly 7700 pcb-n0a00c-spk speaker assembly capacitors c265-c270 153f-102j-5-im cm 50v 1000pf 5% rl 5x7 wafers / terminals p260,p261 2101-9100-0 jm2422-4m wafer p262 2101-9090-0 jm2422-2m wafer m260 ...

  • Page 55

    67 r516 4701-221j-c rcf 1/8w 220r 5% ats r517,r528,r536 4701-151j-c rcf 1/8w 150r 5% ats r519,r520,r537 4701-471j-c rcf 1/8w 470r 5% ats r521 4701-680j-c rcf 1/8w 68r 5% ats r522 4701-222j-c rcf 1/8w 2.2k 5% ats r523 4701-333j-c rcf 1/8w 33k 5% ats r524 4701-562j-c rcf 1/8w 5.6k 5% ats r525-r527 470...

  • Page 56

    68 c947 157f-474m-5-gm ce 50v 0.47μf 20% rl 4x7 c948 157f-105m-5-gm ce 50v 1μf 20% rl 4x7 c950,c968,c974,c976 150f-223k-2-fd cc 50v 0.022μf 10% at c951 157f-225m-5-gm ce 50v 2.2μf 20% rl 4x7 c953,c954 153f-272j-5-jm cm 50v 2700pf 5% rl c959,c960 157d-226m-5-gm ce 16v 22μf 20% rl 4x7 c961,c962 *ah 15...

  • Page 57

    69 ceramic filters m902-m904 2701-0010-1 cf10.7 +-30 m911 2701-0680-0 cf 450 +-1 tuners m901 *ah 1300-0810-0 tuner env16102g1 ul ver m901 *c 1300-0800-0 tuner env16102gi ce ver miscellaneous 4131-7701-0 antenna washer transistors q902 4851-9230-5 tr 2sc1923-0 hfe 70-140 q903,q945 485a-114e-5 tr dta1...

  • Page 58

    70 r944 4701-104j-c rcf 1/8w 100k 5% ats r945 4701-392j-c rcf 1/8w 3.9k 5% ats r946 4701-332j-c rcf 1/8w 3.3k 5% ats r947,r948 4701-103j-c rcf 1/8w 10k 5% ats r949 4701-332j-c rcf 1/8w 3.3k 5% ats r950 4701-684j-c rcf 1/8w 680k 5% ats r951 4701-102j-c rcf 1/8w 1k 5% ats r952,r953 4701-223j-c rcf 1/8...

  • Page 59

    71 q407,q410 4860-0770-5 tr 2sc2878 (a,b) rl q408,q409,q411,q412 485c-114e-5 tr dtc114es resistors r402 4701-102j-c rcf 1/8w 1k 5% ats r403,r404 4701-222j-c rcf 1/8w 2.2k 5% ats r405-r408 4701-103j-c rcf 1/8w 10k 5% ats r409 4701-203j-c rcf 1/8w 20k 5% ats r410 4701-151j-c rcf 1/8w 150r 5% ats r411-...

  • Page 60: Exploded View

    72 exploded view ! ! ! 0148 0120 0121 0123 0193 0148 0140 0148 0147 0148 0146 0138 0304 0146 0310 0178 0310 0162 0147 0142 0148 0148 0142 0155 0134 0133 0142 0148 0102 0142 0187 0139 0141 t002 0306 0101 0148 0126 0127 0143 0142 0155 0147 0146 0142 0104 0110 0106 0148 0113 0210 0112 0122 0131 0137 01...

  • Page 61: Exploded View Parts List

    73 0101 1403-5161-1 bottom chassis t-741 1 0102 1403-5173-2 rear panel t-741 1 0103 1403-5183-0 top cover t-741 1 0104 1403-6511-0 subfascia t-741 1 0105 1403-6381-0 fascia t-741 1 0106 4154-0301-0 input bezel t-760 1 0109 4134-9051-0 bracket angle 2 0110 4134-9061-0 bracket phones 1 0112 4154-0311-...

  • Page 62

    0146 2904-3008-0000 m3x8mm binding head 15 0147 2954-3006-0000 3x6mm b-tite (yel.Zn) 5 0148 2954-3008-0000 tapping 3x8mm b-tite 34 0154 2954-2606-3000 screw bh 2.6x6 black 9 0155 2954-2608-3000 screw bt 2.6x8 black 19 0162 2904-3006-0000 screw m3x6 1 0168 2900-3010-3030 screw m3x10 w/s&f 11 0176 310...

  • Page 63: Packing Diagram

    75 packing diagram 45 44 43 36 37 38 36 41 42 40 39 46 item part no. Description q’ty 36 1490-3584-2 polyform endcap 2 37 1497-1072-4 unit polybag 1 38 1497-1162-0 fascia cover 1 39 4060-0530-0 batteries 2 40 2107-0661-1 300 ohm t antenna 1 41 8912-0001-0 remote control handset 1 42 2103-6101-0 rf c...

  • Page 64: Ser

    Ser vice manual © nad 2001 t 741 surround sound receiver nad electronics international toronto.