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NAD T752 Service Manual

Other manuals for T752: Owner's Manual

Summary of T752

  • Page 1

    Nad service manual t 752 t 752 av surround sound receiver av s u r r o u n d sound receiver draft date: 08 oct, 2002.

  • 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 33-0160001-00-48 fuse 8a 250v time lag 5x20 mm ul/csa f751*c 33-0131002-00-48 fuse 5a 250v time lag...

  • 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) ≤ 0.1 % input sensitivity (ref. 8 ohms, 1 khz) 200 ± 20 mv s/n ratio (a-wtd, 1khz, 1 w, 8 ohm, sl/sr) ≥ ≥ ≥ ≥ ≥ - 80 db ...

  • Page 5

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

  • Page 6

    6 1 2 3 4 5 6 7 8 9 19 20 11 12 13 14 15 16 17 18 10 2 3 1 15 12 14 5 6 8 11 9 10 16 7 4 13 front panel rear panel / front panel view rear panel 1. Fm & am antenna 2. Main in / audio pre-outs / subwoofer out 3. Monitor out 4. Cd input 5. Disc input 6. Ir input & output 7. Component video in & compon...

  • 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. 1 4 5 6 7 8 9 10 2 3 2. Pull both sides of the top cover slightly outwards 11 and tilt approx. 35 ° and then remove in th...

  • Page 8: Wiring Diagram

    82-0116435-00-95 cable assy 1 way #16 ul 1672 brown l=400mm c able a ss y 3 way s # 2 6 u l2 8 77 l=1 50 8 2- 03 2 6135 -0 7- 98 video 6 input board j721b j709b t o s ec o ndary tran s f o rmer to tran s f o rmer t herm os tat to s e co ndary tran s f o rme r to pirmary t ran s f o rmer 8 2-142 6 1 ...

  • Page 9

    Part no. Description location start end normal front and center amp board 82-1224135-02-98 cable assy 12 ways awg=26 2.5p ul2877 l=120mm j503a fr & c amp board surr amp board normal surround amp board 82-0318235-03-98 cable assy 3 ways awg=18 3.96p ul1007 l=180mm j504b surr amp board fr & c amp boar...

  • Page 10

    Normal secondary board 82-1426135-00-98 cable assy 14 ways awg=26 2.5p ul2877 l=420mm j782a secondary board main board normal trigger board 82-0326135-03-98 cable assy 3 ways awg=26 2.5p ul2854 l=150mm j304b trigger board audio board 82-0826135-00-98 cable assy 8 ways awg=26 2.5p ul2877 l=480mm j350...

  • Page 11: Block Diagram

    9 os d l c747 63 pin 4 14 b e a c s peaker o ut p ut o ut p ut sp eaker pin ( st/mo, mute, s meter ) c e/data/clk , rdsbus v fd driver cpus s tere o m od e ac3 m od e m ulti ch in by cpu co ntr o l 4966 vfd (vacuum florescent display) by cpu 4966 c ontrol l ine-out l ine- ou t c d v 1 v 2 v3 v3 v4 v...

  • Page 12: Amplifier Adjustment

    10 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 13: Pcb Layout

    11 pcb layout audio board - component side audio board - copper side.

  • Page 14

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

  • Page 15

    13 dsp board - copper side dsp board - component side.

  • Page 16

    14 front/center amplifier board.

  • Page 17

    15 surround amplifier board.

  • Page 18

    16 key board - component side key board - copper side.

  • Page 19

    17 main board.

  • Page 20

    18 multi-channel board.

  • Page 21

    19 secondary/power switch/led board power supply board (standby).

  • Page 22

    20 pre-out board.

  • Page 23

    21 speaker terminal board trigger board video 6 board.

  • Page 24

    22 s-video board composite video board - component side - copper side.

  • Page 25: Schematic Diagram

    23 u303 ic-lc4966 u302 ic-lc4966 u301 tc9273 j305 jumper wire to t rigger j305a j617a jumper wire to pre-out j617 jumper / short pad dt a144esa dtc144esa e c b r v1 in l r v2 in l r v3 in l r v 3 o u t l r v4 in l r v 4 o u t l r v5 in l r cd n l schematic diagram audio switch resistors : unless oth...

  • Page 26

    24 e c b 2sa933 monitor out video 5 in video 4 out video 3 out video 4 in video 3 in video 2 in u4201 lc4966 u4202 ba7625 video 1 in component video u4301 ba7760fs u4302 74hc4052 u4303 74hc4052 dtc144esa e c b component video 1 component video 2 component video out resistors : unless otherwise speci...

  • Page 27

    25 isc e c b 2sa1015 2sc1815 resistors : unless o therwise specified are carbon film. No te: 1. Resistors, unless o therwise specified, are 1/6w, 5%. 2. All ceramic ca pacitors, unless o therwise specified, are 50v, 10%..

  • Page 28

    26 power supply (secondary) b c e 2sa1016 resistors : ce-cermic case, mo-met al oxide, unless o therwise specified are carbon film. Note: 1 . Resistors, unless otherwise specified, are 1/6w, 5%. 2. Components marked “ ” are sa fety critial parts..

  • Page 29

    27 power supply (stand by) t o power suppl y (secondar y) power transformer power st and by e c b 2sa1815 10% *ah (ul only) *ah *c *ah *c 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 t h e r w is e s p e c if ie d , a r e 1 /6 w , 5 % ...

  • Page 30

    28 trigger r disc in l dtc123esa e c b resistors : unless otherwise specified are carbon film. No te: 1. Resistors, unless o therwise specified, are 1/6w, 5%. 2. All ceramic ca pacitors, unless o therwise specified, are 50v, 10%..

  • Page 31

    29 video 6 video 6 resistors : unless o therwise specified are carbon film. No te: 1. Resistors, unless o therwise specified, are 1/6w, 5%. 2. All ceramic ca pacitors, unless o therwise specified, are 50v, 10%..

  • Page 32

    30 u4101 lc74763-9012 u4104 lc4966 u4102 ba7625 u4103 ba7625 e c b 2sa933 e c b 2sc1740 e c b 2sc2878 dtc144esa dtc123esa dt a144esa e c b s-video resistors : unless o therwise specified are carbon film. No te: 1. Resistors, unless o therwise specified, are 1/6w, 5%. 2. All ceramic ca pacitors, unle...

  • Page 33

    31 front right channel front left channel fl spk fr spk center spk center channel e c b 2sa1016 2sc2362 b c e 2sa1606 2sc4159 b c e 2sa2031 2sc5669 e c b 2sc1740s e c b 2sb772 e c b 2sd600 dtc123esa e c b front / center amplifier no te: 1. Resistors, unless o therwise specified, are 1/6w, 5%. 2. All...

  • Page 34

    32 surround amplifier surround right channel surround left channel sl spk sr spk e c b 2sc2362 e c b 2sa1015 2sa1815 b c e 2sa1606 2sc4159 b c e 2sa2031 2sc5669 e c b 2sd600 dtc123esa e c b resistors : ce-ceramic case, mo-met al oxide, unless otherwise specified are carbon film. No te: 1. Resistors,...

  • Page 35

    33 cutting line for folded page! Digital in/out u1001 cs49326-cl u1009 74lvc574 u1008 74lvc574 u1014 74lvc245a u1017 ic-74hc251 8ch mul tiplexer digit al/audio interf ace receiver 2 i/p select or oct al bidirectional transceiver oct al bidirectional transceiver oct al d-flip flop oct al d-flip flop ...

  • Page 36

    34 cutting line for folded page! Vd201 vacuum florecent display 16-bt-93gnk e c b 2sc1815 u207 hcf4094b u206 hcf4094b u205 hcf4094b u208 74hc4051 u209 74hc245 u201 8-bit microcontroller plcc m6759 eeprom 2k byte u202 8-bit microcontroller plcc m6759 u203 pt6306 64-bits high voltage display driver ic...

  • Page 37

    35 cutting line for folded page! Multi-channel board pre-out board center muting -7.5v supply +7.5v supply sub b.Surr r b.Surr l surr l front l front r surr r e c b 2sc2878 e b c ss8050 ss8550 e c b rn1241 dtc144esa dtc114esa dta114esa dta144esa e c b hi voltage analog function sw. Multi-ch / pre-ou...

  • Page 38

    36 cutting line for folded page! T o front power amp to t u n e r to m u l t i- c h to p r e -o u t to v id e o 6 t o audio switch to s u r r o u n d power amp to s -v id e o to d s p e b c ss8050 t o composite video ic block diagram 74hc157 dsp board: u1004 1 15 select strobe 2 1a 1b 4 1y 3 5 2a 2b...

  • Page 39

    37 74lvc245 dsp board: u1002, u1003, u1014 74vhc245 keyboard: u209 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 ...

  • Page 40

    38 dac serial input interface interpolation filter interpolation filter analog filter analog filter mutec aoutl aoutr rst lrck sdata mclk external mute control sclk/dem1 dac de-emphasis dem0 dif0 dif1 cs4340 dsp board: u1022 data 7:0, emad 7:0, gpio 7:0 cs parallel or serial host interface cmpclk, s...

  • Page 41

    39 vdd cont a cont d in/out in/out out/in sw d sw c out/in in/out out/in out/in in/out vss cont b cont c 14 8 9 10 11 12 13 1 7 6 5 4 3 2 sw a sw b sw a sw d sw b sw c njm5532 dsp board: u1010~u1013, u1023 & u1025 multi-channel: u605~u608 pre-out board: u609~u612 njm4558d surround amp board: u801 1 ...

  • Page 42

    40 m24c16 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 pt6306 keyboard: u203 pcb 44 45 43 37 36 41 38 rdio bk latb ldio rdin rdout ldin ldout dir clk sq1 sq64 qb1 hvo1 hvo23 g qb23 direction con...

  • Page 43: Com Out/in

    41 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

    42 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: Com "y" Out/in

    43 74hc4052 component video board: u4302 & u4303 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 ba7625 composite video board: u4202 s-video board: u4102 & u410...

  • Page 46

    44 lc74763 s-video board: u4101 serial- parallel converter composite synchro- nization signal control afc circuit sync separator sync detector composite synchronizat- i on s ig na l separator control timing generator character output control background control vi de o ou tp ut c on tro l synchroniza...

  • Page 47

    45 2 2 28 14 3 4 5 6 7 8 9 10 11 12 13 level shifter shift register la tch circuit level shifter la tch circuit 27 26 25 24 23 22 21 20 19 18 17 16 15 l-s1 l-s2 l-com1 l-s3 l-s4 l-com2 l-s5 l-s6 l-com3 l-s7 l-com4 st vss gnd vdd r-s1 r-s2 r-com1 r-s3 r-s4 r-com2 r-s5 r-s6 r-com3 r-s7 r-com4 data ck ...

  • Page 48

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

  • Page 49: Exploded View Parts List

    47 exploded view parts list item part no. Description qty. 1 10-0752001-00-10 window lens 1 2 10-0752002-71-00 volume knob assembly 1 3 10-0752005-71-00 volume bezel 1 4 10-0752007-01-00 video cover 1 5 10-0752011-00-00 led lens 1 6 10-0752012-01-00 racker button 2 7 10-0752015-01-00 led bezel 1 8 1...

  • Page 50

    48 item part no. Description qty. 51 14-0401002-04-00 screw m4 x 10 blk-plt 4 52 15-0400320-07-20 nut m4 x 3.2 4 53 15-0900220-11-30 nut m9 x 2.2 1 54 16-0320560-09-20 spring washer 18 55 16-0350080-04-35 steel washer 4 56 16-0400074-10-31 spring washer 4 57 16-0400100-08-25 steel washer 4 58 17-050...

  • Page 51: Electrical Parts List

    49 electrical parts list front and center amplifier board pcb assembly 80-0907520-40-00 front and center amp assembly surround amplifier board pcb assembly 80-0907520-18-00 surround amp assembly dsp board pcb assembly 80-0907520-65-00 dsp assembly audio board transistors q301,q303,q307,q309 21-00001...

  • Page 52

    50 reference no. Part no. Description rcs jacks m431-m432,m434 34-4032020-00-60 rca 3 g-bl-r gold rs-354g-18 switch s4301 35-4102209-00-67 sw slide 2p2t jsk022n09-g09 digital board fibre optical j1008 26-6691386-00-16 fibre optic transmitter gp1fa550tz j1005-j1006 26-6701380-01-16 fibre optic receiv...

  • Page 53

    51 reference no. Part no. Description u208 27-0140510-18-00 i.C. Mux/demux m74hc4051mir u209 27-0324591-18-00 ic octal bus transceiver 74vhc245m u210 27-2300225-00-00 i.C. Eeprom 2k byte 250ns m24c16-bn6 crystal x201-x202 28-5221200-06-19 crystal 22.1184mhz 30ppm hc-49s ic socket u201a 34-6244000-00...

  • Page 54

    52 reference no. Part no. Description capacitors c701,c705-c706,c716 22-3102032-00-28 cap elec gr 1000uf 25v 20% c702,c719,c723 22-3101022-00-43 cap elec ss 100uf 16v 20% c704 22-3332032-00-28 cap elec gr 3300uf 25v 20% c707,c721,c724 22-3222032-00-34 cap elec gs 2200uf 25v 20% c710 22-3470052-00-43...

  • Page 55

    53 reference no. Part no. Description pre-out board diodes d602,d604 20-3275902-00-01 diode zener bzx55 7.5v 1/2w 5% d605-d609, d611-d615 20-0000000-00-13 diode sw 4ns do35 in4148 transistors q605 21-0000140-00-11 xtr npn hfe 120 100mhz ss8050c q607 21-0100131-00-11 xtr pnp hfe 170 1.5a ss8550c q608...

  • Page 56

    54 reference no. Part no. Description resistors r751 23-5228330-00-00 res fusible 0.22 ohm 10% 1/2w r754*ah 23-0395230-00-00 res cf 3.9m ohm 5% 1/2w relay m751*c 32-3112100-02-97 relay 12vdc/10a spst pcb omi-ss-112lm m751*ah 32-1012100-01-97 relay 12vdc/10a 1p1t diode d751 20-0000000-00-13 diode sw ...

  • Page 57

    55 reference no. Part no. Description capacitors c790-c791 22-3123072-00-41 cap elec lp 12000uf 80v 20% c781-c789 22-4210402-00-31 cap mpf 0.1uf 63v 5% resistors r784-r785 23-2228232-00-00 res mo 0.22 ohm 5% 1/2w r790,r793 23-4228280-08-20 res ce 0.22 ohm 5% 5w r781-r783 23-5228330-00-00 res fusible...

  • Page 58

    56 reference no. Part no. Description ics u4101 27-5574763-21-02 i.C. Osd lc74763-9012 u4102,u4103 27-5076250-21-23 i.C. Av switch ba7625 u4104 27-9496600-21-02 i.C. Quad bilateral switch lc4966 crystals x4101 28-5143200-06-19 crystal 14.318mhz 30ppm hc-49s x4102 28-5177200-06-19 crystal 17.73447mhz...

  • Page 59

    57 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, ce-ceramic case. Capacitors c4201-c4203, c4205, c4207, 22-3226052-00-43 cap elec ss 2....

  • Page 60: Packing Diagram

    58 packing diagram 1 3 4 5 6 11 10 9 8 7 2 item part no. Description qty. 1 64-0200001-01-00 polybag manual 1 2 61-0752004-42-99 owner’s manual gb/f/d/nl 1 61-0752004-43-99 owner’s manual e/i/p/s 1 31-6472801-00-28 am loop antenna 1 31-6407520-00-98 fm antenna 1 34-0081004-00-48 300 to 75 ohm adapto...

  • Page 61: Version History

    59 version history serial number software ver. Pcb assembly version r28t75200001-r28t75200050 8.3 a6 pcb assembly keyboard, dsp board, trigger board, main board, video 6 board, pre-out board, multi-channel board, secondary board, led board, digital board, power switch board, component video board. A...

  • Page 62: Notes:

    60 notes:.

  • Page 63: Service

    60 service manual t 752 av s u r r o u n d sound receiver nad electronics ltd london © nad 2002.