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NAD T 751 Service Manual

Summary of T 751

  • Page 1

    Nad service manual t 571 t 571 dvd / vcd / cd player dvd / vcd / cd player draft date: 30 oct, 2002.

  • Page 2

    Contents section 1 . . . .Summary section 2 . . . .Cabinet & main chassis section 3 . . . .Electrical section 4 . . . .Mechanism section 5 . . . .Replacement parts list.

  • Page 3: Section 1

    Section 1 summary contents product safety servicing guidelines for video products ........................... 1-3 servicing precautions .................................................................................................. 1-4 • general servicing precautions • insulation checking prodedu...

  • Page 4

    1-3 prior to shipment from the factory, the products are strictly inspected to conform with the recognized product safety and electrical codes of the countries in which they are to be sold. However, in order to maintain such com- pliance, it is equally important to implement the following precaution...

  • Page 5

    1-4 fig. 3 safety check after servicing examine the area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions. Afterwards, perform the following tests and confirm the specified values in order to verify complianc...

  • Page 6: Specifications

    1-5 specifications dvd video player power supply ac 120 v, 60 hz (t571ah) ac 110~240 v, 50/60 hz (t571c) power consumtion 16 w mass 5.7 kg(12.6 lbs) external dimensions 440 x 118 x 423 mm (w x h x d) signal system ntsc (t571ah) pal (t571c) laser (dvd) semiconductor laser, wavelength 650 nm (cd) 780 ...

  • Page 7: Section 2

    2-1 section 2 cabinet & main chassis contents 1. Disassembly .........................................................................................................................2-2 cabinet disassembly .................................................................................................

  • Page 8: Disassembly

    2-2 disassembly caution before starting servicing electronic parts are susceptible to static electricity and may easily and damaged, so do not forget to take a proper grounding treatment as required. Many screws are used inside the unit. To prevent missing, dropping, etc. Of the screws, always use a...

  • Page 9

    2-3 (l1) (l1) (b) (b) (c) (c) (c) power code power circuit board main chassis ma ass'y dpm1 bracket main jack circuit board (f) (f) (f) (f) main circuit board (b) (b) (d) (e) (d) (d) (d) (e) (e) (b) (b) (g) (g) (g) (g) (g) (g) fig. 2-4 fig. 2-5 1. Disassemble main circuit board, jack circuit board, ...

  • Page 10: Exploded Views

    2-4 exploded views 1. Cabinet and main frame section 465 465 250 462 462 300 465 260 465 a46 a47 463 463 275 463 463 463 467 a48 463 463 463 463 463 a00 a43 280 285 262 452 452 dig901 pbt oo 283 a 5 4 3 2 1 b c d.

  • Page 11

    2-5 2.Packing accessory section battery 808 packing sheet 804 packing optional parts 803 811 812 owner's manual 810 cable set ass'y 801 remocon 900 box carton 802 packing 803.

  • Page 12: Section 3

    3-1 section 3 electrical contents electrical troubleshooting guide ......................................................................3-2 1. Power(smps) circuit ...............................................................................................................3-2 2. µ-com circuit........

  • Page 13

    3-2 electrical troubleshooting guide no 5v_d or 5v_a . No 5.2va. Is 5.2va section working? (is the power ctl at pin6 high/low?) is oscillation present at the base of q108? Replace q108. Check d109, c123, r125, r124. Replace r102. Replace bd101. (bridge rectifier) is r102(r104) normal? Is about ac 10...

  • Page 14

    3-3 replace main b/d refer to front part replace ic502 reconnect it. 2. µ-com circuit a. No power does logo appear on the screen? Is oscillation of x501 normal? Are ic501 pins 193, 80 8 and 81 normal? Do “hello” appear at fld? Is p3901 connected normally? Is p3901 pin 8, 9, 18 normal? The waveform o...

  • Page 15

    3-4 b. Audio abnormal d. Open/close abnormal check the connection of p3901. Check ic301 pins 93, 94. Check audio jack. Yes (if ok) yes no no yes yes (if ok) yes yes (if ok) yes (if ok) yes (if ok) refer to audio part. Refer to decoder part. Refer to pantera part. Replace b/d. Check front. Reconnect ...

  • Page 16

    3-5 e. Picture abnormal check the disc. If ok yes (if ok) yes (if ok) refer to servo part check dsp check pantera replace b/d picture abnormal f. Disc error check disc yes (if ok) yes (if ok) refer to servo part replace b/d disc error.

  • Page 17

    3-6 power is on does toshiba logo appear on the screen? Does the moving picture of the dvd disc play on the screen normally? Is pantera data signal normal? Is error signal normal? Is pantera data signal normal? Is clock normal? Does the audio sound output from pantera decoder? Does the moving pictur...

  • Page 18

    3-7 no no no start does remote control work normally? Do all the buttons work normally? Check waveform of ic901 pin 21, 22. Check waveform of ic901 pin 27. Is digitron on normally? Led on? Check waveform of ic901 pin 6. Is oscillation of x901 normal? Is waveform of ic901 pin 40 normal? Check wavefor...

  • Page 19

    3-8 does signal pulse input to ic201 pins 58, 59 when the power is on? Does signal goes "high" to ic201 pin194 when the power is on? Does ttl pulse output to ic201 pins 140, 142? Does 33.8688mhz clock input to ic201 pin 63? Is ic201 pins 83, 84, 88, 89 voltage about 2.2v? Replace ic201 (ic206 solder...

  • Page 20

    3-9 does tray open or close? Does the pick-up slide inner or outer track? Fig.1. Sled driver waveform fig.2. Focus driver waveform does the voltage change at pmd03 pins 15, 16 more than 2v on the basis of 3.8v? Pressing the open/close key repeatedly, check the voltage of ic2m1 pins 13, 14 change 0v ...

  • Page 21

    3-10 focus on? Check the focus error moving the lens up and down. (ic2a1 pin 42) does the ttl level change at ic201 pin 78 and 132 moving the lens? Does the disc turn? Ic201 pin169 is "high"? Is ok the track jump. Does the signal pulse appear at ic2a1 pins 39, 29? Does the screen appear? Open/close ...

  • Page 22

    3-11 see the eye-pattern vivid? Does the sawtooth waveform emit at ic2a1 pin 41? Does the 1.6v emit? Check rf eye-pattern. Rf : 1.5-1.6v(ic2a1 pin 57) fig.5. Rf waveform check ic2a1 pins 5, 6, 7, 8. No signal: pick-up is defective replace ic201. Check ic201 pin84. No signal at ic201 : ic201 is defec...

  • Page 23: Block Diagrams

    3-12 block diagrams 1. Overall block diagram m m disc spindle mot or loading mot or deck m echani sm cd: a,b, e, f dvd: a,b,c,d, dvd; rf cd: a,b, e, f dvd: a,b,c,d, dvd; rf pick up ic205 dram 16bit 4m ic201 hy25d801c cd / dvd dsp ic501 p antera - ii /2e ic901 upd78032 from fl displa y key input remo...

  • Page 24

    3-13 2. Power(smps) block diagram 5v _ d 5 v_a -27 v a vf + recti fi er l i ne fi l ter swi tchi ng tr trans feed b. Reg(8v) 8v 5.2 va vf - rectifier(fld) rectifier(9v) rectifier(5.2v) lpf lpf rectifier(14v) lpf 12 va pwr on/off reg(3.3v) reg(3.3v) 3.3 v 3 .3 v,3.3v_m rectifier(3.8v) lpf -12 v a.

  • Page 25

    3-14 88 sens, fok, sld_fg, msda t0, defect ,dsp_sense ic2m1 ka3017 spindlemotor ,loadingmotor , actuator driver cd: a,b,c,d / e, f 44 44 mirr,tzc 88 55 33 33 sqso, sqck, scor scor 66 xla t , s_clk, s_da t a ucom i/f focus, tracking, loading, sled spindle m/d pick up mck ic206 dvdsp -3301 cd / dvd ds...

  • Page 26

    3-15 4. Audio block diagram ic401 pcm1716 audio dac ic402 lpf & buf fer njm4580d op amp u-com i/f a_0wt3 /srst dac comm_da t a comm_clk dac_cs lrck da_bck da_xck l r l r mpeg i/f.

  • Page 27

    3-16 5. Mpeg block diagram ic501 p antera -2 ic301 xc9572vl cpld i/o por t 72 ic304 sdram 16/32bit 64m ic502 93c46 eeprom ic3f1 flash memor y ic302/ic303 la tch ad[0:7] 8 dsp i/f dvd[0:7] 8 la[0:3] 4 sclk,sda t a sqck,sqs0 reqp sdclk1,psync dsp_int sense /dsp_cs ad[ 00:19] rf & mot or i/f mirr ldon ...

  • Page 28

    Notes) warning notes) parts that are shaded are critical notes) with respect to risk of fire or notes) electricial shock. 470 µ f/2.3v '01. 09. 21 r10581b t571c/t571ah 3-17 3-18 circuit diagram 1. Power(smps) circuit diagram note : 1. Shaded( ) parts are critical for safety. Replace only with specif...

  • Page 29

    3-19 3-20 5 5 6 spindle servo loop rf signal focus servo loop tracking servo loop sled servo loop waveform t571c/t571ah 2. Dvd dsp circuit diagram dvd/cd picture audio abnormal mpeg interface line µ-com interface data µ-com interface adress cd/dvd picture audio abnormal tracking/focus servo fail tra...

  • Page 30

    3-21 3-22 3. Drive & rf circuit diagram 4 1 6 2 3 1 waveform spindle servo loop turn table loop focus servo loop tracking servo loop sled servo loop t571c/t571ah turntable not operate tray loading speed control turn table speed control spindle motor unstable actuator spindle sled not operate dvd las...

  • Page 31

    4 4 3 7 5 2 6 waveform optical/coaxital out y/pb/pr(component) y.C(s-vhs) audio l/r out cvbs t571c/t571ah 3-23 3-24 4. Pantera circuit diagram no power on audio dac interface system not operate dsp interface line spindle motor unstable system not working or digitron not display..

  • Page 32

    3-25 3-26 • waveforms ic2a1 pin 42, focus error ic2a1 pin 36, pi ic2a1 pin 41 tracking error ic501 pin 114 component y ic2a1 pin 41 vbr tracking error ic2a1 pin 57, rf ic201 pin 88, sled drive(fmo) ic201 pin 18, sled fg ic2a1 pin42, focus error(in focus search) ic201 pin 83, focus drive(fdo) ic501 p...

  • Page 33

    3-27 3-28 5. Memory circuit diagram t571c/t571ah program download fail digitron abnormal not used not power on not memoried setup menu turntable not operating “no disc” display tray not open/close tray not closed pick-up not initial operating disc detec error disc number detect error digitron all no...

  • Page 34

    3-29 3-30 6. Timer & key circuit diagram t571c/t571ah system not operate remocon not operate power not control digitron abnormal digitron abnormal.

  • Page 35

    3-31 3-32 7. A/v circuit diagram l r t571c/t571ah q401 is defective 2ch. Audio out bad. Ic401 is defective. 2ch audio out bad. Ic401 is defective. 2ch audio out bad. Ic403, q404 are defective. Digital data out bad..

  • Page 36

    3-33 3-34 8. A/v jack circuit diagram (t571ah only) t571c/t571ah component, s-video out can,t be changed..

  • Page 37

    3-35 3-36 9. Scart circuit diagram (t571c only) t571c/t571ah component, s-video out can,t be changed..

  • Page 38

    3-37 3-38 level(v) mode pin no. 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 43 44 45 46 47 48 49 50 51 52 53 3.18 1.3 1.4 2.2 1.5 0 1.5 1.4 1.6 3.1 0.7 0.15 0.15 0 0 1.7 1.4 0 1.5 1.6 0 1.6 0 3.1 1.7 1.4 3.1 1.5 0.15 0 0.7 1.5 ...

  • Page 39

    3-39 3-40 ee play mode pin no. 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 1 2 3 4 5 6 7 8 1.40 3.20 1.60 0.00 0.00 0.00 5.00 0.00 3.10 3.10 3.10 3.10 2.53 4.24 5.0...

  • Page 40

    3-41 3-42 printed circuit diagrams 1. Main p.C.Board location guide.

  • Page 41

    3-43 3-44 location guide 2. Av jack p.C.Board 4. Front p.C.Board location guide 3. Smps p.C.Board.

  • Page 42: Contents

    • top view..................................................4-1 • top view(without tray disc) .................4-1 • bottom view ...........................................4-1 1. Holder assembly clamp..................4-2 1-1. Plate clamp ......................................4-2 1-2. Magnet clamp ....

  • Page 43

    4-1 deck mechanism parts location starting no. 1 1,2 1,2,3 1,2,3,4 6 6 6,7 6,7,10 6,7,10,11 6,7,8,9,10, 11,12 1 1 1 1,17 1,17 1 1,15,16,17, 18,19,20 1,14 6 6,24 6,24 6,24,26 6,24,26 6,24,26,28 6,28 1,6,14,23, 24,25,26, 27,28,29, 30 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...

  • Page 44: Deck Mechanism Disassembly

    4-2 deck mechanism disassembly 1. Holder assembly clamp(fig. 4-1) 1) release 3 screws(s1). 2) unlock the connectors (c1), (c2) from the hook(h1). 1-1. Plate clamp 1) hold and fix the upper clamp under the holder assembly clamp, and then turn the plate clamp to the counterclockwise direction(arrow(a)...

  • Page 45: Deck Mechanism Disassembly

    4-3 deck mechanism disassembly pcb assembly junction (l3) (c7) (s7) (s7) (s7) (s8) gear assembly rack rubber damper pick up assembly general gear middle base pu(outsert) rubber damper rubber rear rubber rear gear assembly feed gear middle gaer assembly rack pick up assembly general motor assembly sp...

  • Page 46: Deck Mechanism Adjustment

    4-5 deck mechanism adjustment 1. Tools and fixtures for svc • for svc program down-load • for t-skew and r-skew adjustment 2. Install process 1. Connect fig. 1, 2, 3 as fig. 7. 2. Plug out the power cord of dvd set. 3. Connect ffc cable(fig.2) to the connector on dvd set(fig.8) 4. Connect printer ca...

  • Page 47

    M e m o 4-6 deck mechanism adjustment 3. Adjustment procedure 1. Insert disc(only open/close key pressing) 2. Wait until the sector display is about 200,000 (fig.11) 3. Adjust r-skew adjusting point until the error rate has minimum rate with l-wrench (3mm). 4. Adjust t-skew adjusting point until the...

  • Page 48: Exploded Views

    4-7a exploded views 1. Cabinet and main frame section 465 465 250 462 462 300 465 260 465 a46 a47 463 463 275 463 463 463 467 a48 463 463 463 463 463 a00 a43 280 285 262 452 452 dig901 pbt oo 283 a 5 4 3 2 1 b c d.

  • Page 49

    4-7 b 4-8 exploded views 1. Deck mechanism exploded view 016 012 012 014 014 009 013 414 011 008 432 430 430 430 430 031 001 003 004 026 025 002 414 413 413 413 413 413 413 414 414 416 032 034 033 035 416 416 416 416 416 037 038 030 024 022 023 021 020 036 a03 a01 a02 a04.

  • Page 50

    5-1 section 5 replacement parts list model : a:t571ah , b:t571c (nad) run date : 01.10.12 . Mechanical section nsp : not service part s al loca.No part no(lg) a b description specification remarks assembly section a00 6721r-0314c o o deck assy,video dpm1(dvd-cd r/rwc mitsumi ve t nsp a01 4931r-0037a...

  • Page 51

    5-2 s al loca.No part no(lg) a b description specification remarks screw 457 353-051e o o screw special (3x12) 462 353-085e o o screw,drawing + 3 d4.0 l10.0 mswr3/fzmcw-2 463 353-051g o o screw,drawing + 2 d3.0 l8.0 mswr3/fn tb roun 465 353-046k o screw special (3x10 b.K) 465 353-046k o screw specia...

  • Page 52

    5-3 . Electrical section nsp : not service part s al loca.No part no(lg) a b description specification remarks capacitor c101 624-088l o o capacitor,drawing 435d sunil electronics 0.1uf/2 c102 624-088l o o capacitor,drawing 435d sunil electronics 0.1uf/2 c103 0ce157cr610 o capacitor,al.Electrolytic ...

  • Page 53

    5-4 s al loca.No part no(lg) a b description specification remarks c281 0ch7106c611 o o capacitor,fixed tantalum 10uf 6.3v 20% 3216 tp(-) c282 0ch7106c611 o o capacitor,fixed tantalum 10uf 6.3v 20% 3216 tp(-) c284 0ch8476c611 o o capacitor,chip[al. Electrolyti 47uf 6.3v m 85std(cyl) r/tp c285 0ch110...

  • Page 54

    5-5 s al loca.No part no(lg) a b description specification remarks c310 0ch1104k942 o o capacitor,chip[ceramic m/l hd 0.1uf 50v z y5v(f) 1508 r/tp c311 0ch1104k942 o o capacitor,chip[ceramic m/l hd 0.1uf 50v z y5v(f) 1508 r/tp c312 0ch1104k942 o o capacitor,chip[ceramic m/l hd 0.1uf 50v z y5v(f) 150...

  • Page 55

    5-6 s al loca.No part no(lg) a b description specification remarks c532 0ch1104k942 o o capacitor,chip[ceramic m/l hd 0.1uf 50v z y5v(f) 1508 r/tp c533 0ch1104k942 o o capacitor,chip[ceramic m/l hd 0.1uf 50v z y5v(f) 1508 r/tp c534 0ch1104k942 o o capacitor,chip[ceramic m/l hd 0.1uf 50v z y5v(f) 150...

  • Page 56

    5-7 s al loca.No part no(lg) a b description specification remarks ic201 0ihy258010c o o ic,hyundai gdc25d801d 208 qfp bk dsp+serv ic203 0ijr341400c o o ic,jrc njm3414am-te1,3k/reel. Jrc ic204 0istlke009a o o ic,standard logic kic7w53fu kec 8pin sm8 r/tp 2- ic205 0igl440164c o o ic,g-link glt440l16-...

  • Page 57

    5-8 s al loca.No part no(lg) a b description specification remarks led assy&connector,pwb assy led901 0dlau0029aa o o led auk sym3272 (yellow-green,gree p1301 563-602w o o connector assy gil-s/9072st 10 pin 160m/m ul1 p1302 6631r-e009c o o connector assy gil-s/9073st 9pin 160m/m ul106 p3101 6630r3s0...

  • Page 58

    5-9 s al loca.No part no(lg) a b description specification remarks r140 0rd1002f608 o o resistor,fixed carbon film 10k ohm 1/6 w 5.00% ta26 r141 0rd1002f608 o o resistor,fixed carbon film 10k ohm 1/6 w 5.00% ta26 r145 0rd4700f608 o o resistor,fixed carbon film 470 ohm 1/6 w 5.00% ta26 r201 0rh0000c6...

  • Page 59

    5-10 s al loca.No part no(lg) a b description specification remarks r2d4 0rh0000c622 o o resistor,metal glazed(chip) 0 ohm 1 / 16 w 1608 5.00% d r2d5 0rh0000c622 o o resistor,metal glazed(chip) 0 ohm 1 / 16 w 1608 5.00% d r2d6 0rh0912c622 o o resistor,metal glazed(chip) 91 ohm 1 / 16 w 1608 5.00% d ...

  • Page 60

    5-11 s al loca.No part no(lg) a b description specification remarks r352 0rh1000c622 o o resistor,metal glazed(chip) 100 ohm 1 / 16 w 1608 5.00% d r353 0rh1000c622 o o resistor,metal glazed(chip) 100 ohm 1 / 16 w 1608 5.00% d r354 0rh1000c622 o o resistor,metal glazed(chip) 100 ohm 1 / 16 w 1608 5.0...

  • Page 61

    5-12 s al loca.No part no(lg) a b description specification remarks r443 0rh1001c622 o o resistor,metal glazed(chip) 1k ohm 1 / 16 w 1608 5.00% d r444 0rh1001c622 o o resistor,metal glazed(chip) 1k ohm 1 / 16 w 1608 5.00% d r445 0rh1001c622 o o resistor,metal glazed(chip) 1k ohm 1 / 16 w 1608 5.00% ...

  • Page 62

    5-13 s al loca.No part no(lg) a b description specification remarks r903 0rd3301f608 o o resistor,fixed carbon film 3.3k ohm 1/6 w 5.00% ta26 r904 0rd1000f608 o o resistor,fixed carbon film 100 ohm 1/6 w 5.00% ta26 r905 0rd1001f608 o o resistor,fixed carbon film 1k ohm 1/6 w 5.00% ta26 r906 0rd1002f...

  • Page 63

    5-14 s al loca.No part no(lg) a b description specification remarks transistor,resonator,crystal,x-tal t101 642-024e o o transformer,smps sje-024e soojeong wide eer2828 v101 656-004c o o varistor svc681d-10a samhwa 4.O cut x201 6202r-bm01a o o crystal,smd hc-49/sm5h kony chip 33.8688mh x501 6202r-bl...

  • Page 64: Ser

    Ser vice manual ser vice manual t571c t571ah dvd video pla yer t571c t571ah dvd video pla yer t571c t571ah dvd video player models : t571c/t571ah ser vice manual © nad 2001 nad electronics international toronto.