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NAD T955 AH Service Manual

Manual is about: Five channel amplifier

Summary of T955 AH

  • Page 1

    / $ 8 1 $ 0 ( &, 9 5( 6 / $ 8 1 $ 0 ( &, 9 5( 6 7 &$+ $%, / - 4 , ! 5 . ! - % #) 6 2% 3 ‹ 1$' 1$' (/(&7521,&6 ,17(51$7,21$/ 7252172 7 + $ & 5( ,) ,/ 3 0 $ /( 1 1 $ + & ),9( 7 + $ & 5(, ), / 3 0 $ /( 1 1 $ + & ),9( ),9(&+$11(/$03/,),(5.

  • Page 2

    Contents front panel/rear panel view 3 specifications 4 alignment procedure/alignment points 5 wiring diagram 6 schematic diagram 7-12 pcb layout 13-19 electrical parts list 20-33 exploded view 34-36 exploded view parts list 37 packing diagram 38 service safety precautions 1. Replacing the fuses cau...

  • Page 3

    7 ' $ 1 7 ' $ 1 0$,16 ,1 0$,16 ,1 0dqxidfwxuhg'dw h ' h )d e 6huldo 1r1r 'h 6hulh v &$87,2 1 $77(17,2 1 0,1,080 63($.(5 ,03('$1&( 0,1,080 ,03('$1&( '(6 +$87(6 3$ 5/(856 21( 3$ ,5 2+0 0,1 6 3($.(5 21( 3$ ,5 ( 2+0 0,1 6 3($.(5 )86( )86( 63($.(5 63($.(5 63($.(5 63($.(5 63($.(5 63($.(5 63($.(5 63($.(5 6...

  • Page 4

    Specifications continuous average power ≥100 w (20.0 dbw) output into 8 ohms or 4 ohms (min. Power per channel, 20 hz – 20 khz, both channels driven, with no more than rated distortion) rated distortion ≤0.03% (thd 20 hz – 20 khz) clipping power ≥130 w (maximum continuous power per channel). Ihf dyn...

  • Page 5

    Alignment procedure a. Dc offset voltage the dc offset between offset test point and agnd must be within 0+/-20mv. B. Idling current the idling current in the output stage of the poweramp should be set to 25ma+/-5ma per pnp-npn transistor pair( this means the mid point voltage is 4mv with down limit...

  • Page 6

    Vss1 agnd1 agnd1 vpp1 isc1 vss1 agnd1 agnd1 vpp1 acoff1 dgnd sc led1 isc1 vss2 agnd2 agnd2 vpp2 acoff2 dgnd sc led2 isc2 vss3 agnd3 agnd3 vpp3 acoff3 dgnd sc led3 isc3 vss4 agnd4 agnd4 vpp4 acoff4 dgnd sc led4 isc4 vss5 agnd5 agnd5 vpp5 acoff5 dgnd sc led5 isc5 dgnd stby +5.5v sc +5. 5 v th er mal a...

  • Page 7

    Agnd led sc isc vss offset agnd agnd tp3 offset tp2 tp1 acoff dgnd vpp tp3 th 2 agnd egnd tp1 tp2 -15va agnd +15va th1 th2 th1 -15va +15va -15va vcc +15va vss +15va +15va vcc vss -15va +15va -15va -15va t o connect ion board /1/4w /1k v /2w /2w /2w /1w /1kv /1kv /1k v /25v /25v /1w /1w /1w /1w /1/4w...

  • Page 8

    Isc1 v-1 agnd1 agnd1 v+1 acoff1 dgnd sc led1 isc2 v-2 agnd2 agnd2 v+2 acoff2 dgnd sc led2 isc3 v-3 agnd3 agnd3 v+3 acoff3 dgnd sc led3 isc4 v-4 agnd4 agnd4 v+4 acoff4 dgnd sc led4 isc5 v-5 agnd5 agnd5 v+5 acoff5 dgnd sc led5 ac2 ac2 ac1 +5.5v sc +5.5v stbyled led1 led5 led4 led3 led2 stbyled stby dg...

  • Page 9

    Sc led3 dgnd led2 sc +5vd stbyled led1 led5 led4 +5v +5v led1 dgnd +5vd dgnd led2 +5v led3 +5v led4 +5v led5 +5v stbyled +5v dgnd dgnd dgnd stbyled dgnd stbyled green +5vd all polyester capacitors are 63v unless noted. All elec. Capacitors are 50v unless noted. All resistor are 1/6w rj13 unless note...

  • Page 10

    Rear pannel 7v 0v neutral live f1 (user accessible fuse) t955 120v/230v table w501&w504 230v 120v no insert insert t15al/250v t7al/250v w502,w503&w505 no insert insert power switch board from power supply board from main transformer to main transformer /275vac tv-8 rating p3 p4 p1 p2 w1 14-97301-01 ...

  • Page 11

    Stby dgnd +5vd sc s402 sssu122na1 s402 sssu122na1 5 6 4 1 2 3 j401 py301-030-100 j401 py301-030-100 p401a 4pin2.54-a300b p401a 4pin2.54-a300b 2 3 4 1 s401 sssu122na1 s401 sssu122na1 5 6 4 1 2 3 - 11 - schematics diagram.

  • Page 12

    120deg thermal autoreset switch yel ul1015 20awg 230mm blk ul1015 20awg 230mm red ul1015 20awg 230mm 0v 33.8v no load 31.3v/5.1a(voltage between pin9 to pin10) 33.8v no load 31.3v/5.1a(voltage between pin10 to pin11) 43.3v no load 40.6v/3.6a(voltage between pin8 to pin10) 43.3v no load 40.6v/3.6a(vo...

  • Page 13

    J10 1 bp1 01 amp board - solder side r164 r166 amp board - component side r188 r123 c140 offset c157 d104 p103a d101 r112 bus101 r131 d129 r106 c136 c153 c1 09 c107 r109 r111 q143 q103 c1 0 5 c103 r107 r105 q1 0 1 r113 c170 c1g1 q144 c 171 r130 d127 r1g1 c110 r114 c106 r108 q104 q1 0 2 c108 q131 r10...

  • Page 14

    Fr o m t ri g b o a rd dgnd stby sc +5.5 v p213b p206b j202 p20 8b j201 p202b j204 p204b j20 3 p210b c237 c239 ac2 q216 ac2 psu board - solder side psu board - component side c223 caution: attention: nad 2006/08/18 utiliser un fusible de rechange de meme type replace only with same type fuse and rat...

  • Page 15

    So f t c li ppi n g d303 t955 front pannel display board led classification c d302 1 ch 1 ch 2 a b d301 dgnd led2 led3 led4 p302a ch 4 d305 ch 5 d306 ch 3 d304 stbyled +5vd led5 led1 r 309 r 308 q 305 r 325 r 307 q3 0 4 r 306 r3 1 1 q 307 r 326 r 310 q 306 w303 vm1.0 08/18/2006 r 314 q3 0 9 r 327 r ...

  • Page 16

    C 501 tr501 vm 1. 0 08/ 18/ 2006 t 9 5 5 s t a ndb y b oa rd n. I. In s e rt w 502 p5 0 6 b p502b p505b w505 w 50 3 w50 4 in s e rt 230v n .I. W5 0 1 120v rl501 d501 ac1 +5 v d ac 2 relay p504b tp standby board p501b p4 p3 w 5 0 2 w 5 0 1 n .I. In s e rt n .I. In s e rt w5 0 5 w 504 n .I. W5 0 3 in ...

  • Page 17

    T955 trigger board vm1.0 08/18/2006 trigger board to psu board p401a j401 s402 s401 - 17 - pcb layout.

  • Page 18

    1 p7 01b vm1.0 08/18/2006 t955 power led board power led board d7 0 1 3 - 18 - pcb layout.

  • Page 19

    Power switch board s90 1 vm1.0 08/18/2006 t955 switch board p1 p2 - 19 - pcb layout.

  • Page 20

    Electrical parts list designato description part type part number footprint d101 zener diode 15v, 1/2w 33-11500-00 dax/.300x.080/.031 d102 recti diode 1n5404 33-25404-01 dax/.600x.200/.059 d103 switch diode 1n4148 33-44148-00 dax/.300x.080/.031 d104 switch diode 1n4148 33-44148-00 dax/.300x.080/.031...

  • Page 21

    Electrical parts list designato description part type part number footprint q117 transistor 2sa970-gr 31-00970-00 to92/100/ecb q118 transistor 2sa1015-gr 31-01015-00 to92/100/ecb q119 transistor 2sc1815-gr 31-01815-00 to92/100/ecb q120 transistor 2sb647-actz 31-00647-00 to92/100/ecb q121 transistor ...

  • Page 22

    Electrical parts list designato description part type part number footprint ic104 voltage ref az431 03-00431-00 to92/100/123 pc101 photocoupler pc817a 03-00817-01 photocoupler_1 pc102 photocoupler pc817a 03-00817-01 photocoupler_1 r101 metal film resistor 680Ω, 1/6w, 5% 07-20681-50 ax/.200x.080/.031...

  • Page 23

    Electrical parts list designato description part type part number footprint r156 metal film resistor 39kΩ, 1/6w, 5% 07-20393-50 ax/.200x.080/.031 r157 metal film resistor 220kΩ, 1/6w, 5% 07-20224-50 ax/.200x.080/.031 r158 metal film resistor 220kΩ, 1/6w, 5% 07-20224-50 ax/.200x.080/.031 r159 metal f...

  • Page 24

    Electrical parts list designato description part type part number footprint r1e6 metal film resistor 1megΩ, 1/6w, 5% 07-20105-50 ax/.200x.080/.031 r1e7 metal film resistor 36Ω, 1w, 1% 07-23609-01 ax/.600x.125/.039 r1e8 metal film resistor 2.2kΩ, 1/6w, 5% 07-20222-50 ax/.200x.080/.031 r1e9 metal film...

  • Page 25

    Electrical parts list designato description part type part number footprint c117 alu electrolytic capacitor 10uf/50v, 20%, 105 06-10051-01 cpcyl1/d.200/ls.200/.031 c118 alu electrolytic capacitor 10uf/50v, 20%, 105 06-10051-01 cpcyl1/d.200/ls.200/.031 c119 alu electrolytic capacitor 1uf/50v, 20%, 10...

  • Page 26

    Electrical parts list designato description part type part number footprint c170 alu electrolytic capacitor 10uf/50v, 20%, 105 06-10051-01 cpcyl1/d.200/ls.200/.031 c171 alu electrolytic capacitor 10uf/50v, 20%, 105 06-10051-01 cpcyl1/d.200/ls.200/.031 c1g1 polyester capacitor 100nf, 10%, 63v 25-1046...

  • Page 27

    Electrical parts list designato description part type part number footprint br208 bridge kbu8d 33-30822-01 bridge/1.010x.290/.063 br209 bridge kbu8d 33-30822-01 bridge/1.010x.290/.063 br210 bridge kbu8d 33-30822-01 bridge/1.010x.290/.063 br211 bridge db104g 33-30142-00 bridge/.400x.500/.047 q201 tra...

  • Page 28

    Electrical parts list designato description part type part number footprint r229 metal film resistor 1kΩ, 1/6w, 5% 07-20102-50 ax/.200x.100/.031 r230 metal film resistor 100Ω, 1/6w, 5% 07-20101-50 ax/.200x.100/.031 r231 metal film resistor 22kΩ, 1/6w, 5% 07-20223-50 ax/.200x.100/.031 r232 metal film...

  • Page 29

    Electrical parts list designato description part type part number footprint c216 alu electrolytic capacitor 10uf/100v, 20%, 105 06-10012-01 cpcyl1/d.200/ls.200/.031 c217 alu electrolytic capacitor 10uf/100v, 20%, 105 06-10012-01 cpcyl1/d.200/ls.200/.031 c218 alu electrolytic capacitor 10uf/100v, 20%...

  • Page 30

    Electrical parts list designato description part type part number footprint p203b housing 5pin3.96-c 13-23905-30 blkcon.156/vh/tm1sqs/w.355/5 p204b connector molex 2145/3215 top entry/9pin 13-25009-00 blkcon.156/molex2145/3215/top entry/9 p205b housing 5pin3.96-c 13-23905-30 blkcon.156/vh/tm1sqs/w.3...

  • Page 31

    Electrical parts list designato description part type part number footprint w201 jumper 10mm 21-06000-00 10mm w202 jumper 15mm 21-06000-00 15mm bus201 busbar 69-010001-0 diode d301 led bl-bubb4274 a 33-50565-00 led/anode/d.200/ls.200/.039 d301 led bl-bubb4274 b 33-50565-10 led/anode/d.200/ls.200/.03...

  • Page 32

    Electrical parts list designato description part type part number footprint r310 metal film resistor 150Ω, 1/6w, 5% 07-20151-50 ax/.200x.100/.031 r311 metal film resistor 150Ω, 1/6w, 5% 07-20151-50 ax/.200x.100/.031 r312 metal film resistor 1kΩ, 1/6w, 5% 07-20102-50 ax/.200x.100/.031 r313 metal film...

  • Page 33

    Electrical parts list designato description part type part number footprint p3 connector ribbon l=95mm 14-95501-03 p4 connector ribbon l=95mm 14-95501-03 w501 jumper 10mm 21-06000-00 10mm w502 jumper 15mm 21-06000-00 15mm w503 jumper 7.5mm 21-10750-00 7.5mm w504 jumper 10mm 21-10101-00 10mm w505 jum...

  • Page 34

    4 a001 a003 a002 s002 s004 s003 a004 s001 s001 s001 s005 a005 a006 s001 - 34 - exploded view.

  • Page 35

    S006 s007 tr01 tr05 tr02 tr03 s007 s008 s009 tr04 - 35 - exploded view.

  • Page 36

    C001 c002 c003 c004 c006 c007 c005 c008 c009 f001 f002 f003 f004 f005 f006 f007 f008 f009 f010 f011 f012 f006 f007 c010 c011 r001 t001 c013 s002 s010 s010 s010 s010 s010 s010 s010 s010 s011 s011 s016 s013 s017 s012 s010 s015 s015 s014 s014 s010 s001 s001 s001 s010 s010 c012 s010 f013 - 36 - exploded...

  • Page 37

    Ref.No part no. Description qty. Ref.No part no. Description qty. A001 70-062005-1 main heatsink 5 f005 77-062002-0 power button bezel 1 a002 01-95501-10 amp module pcb no outputs (ah) 5 f006 76-062001-0 led lens 7 01-95501-20 amp module pcb no outputs (c) 5 f007 75-062001-0 sleeve 7 a003 67-062002-...

  • Page 38

    T955 packing diagram 1 2 3 10 4 5 6 9 7 8 11 1 88-062001-1 carton box 1 2 88-062002-0 bottom polyfoam 1 3 15-10230-20 ac cord 1 4 90-062004-0 epe pad 1 5 00-95500-20 t955 unit 1 6 90-062002-0 non-woven cloth 1 7 90-062003-0 epe bag 1 8 90-062001-0 polyfbag 1 10 89-062003-0 top polyfoam 1 9 90-062004...