Nad-C-426-Service-Manual(1) 电路图 维修手册.pdf

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1、NAD C 426 STEREO AM/FM TUNER C 426 STEREO AM/FM TUNER SERVICE MANUAL RadioFans.CN 收音机爱 好者资料库 - 2 - SERVICE SAFETY PRECAUTIONS 1. Safety check out (Only U.S.A. model) Before returning the product to the customer, make leakage current or resistance measurements to determine that exposed parts are acce

2、ptably insulated from the supply circuit. Parts marked with the symbol are critical with regard to the risk of fire and electric shock. Replace only with parts recommended by the manufacturer. CONTENTS DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3、. . . . . . . . . . . . . . . . PAGE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 REAR PANEL / FRONT PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4、5 DISASSEMBLY INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 WIRING DIAGRAM . . . . . . . . . . .

5、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 ADJUSTMENT POINTS DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 INSTRUMENT SETUP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6、 . . . . . . . . . . . . . . . . . . . . . . . . . 10 ALIGNMENT PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 PCB LAYOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7、. . . . . . .12-14 SCHEMATIC DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-17 IC BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-22 ELECTRICAL PARTS LIS

8、T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23-31 EXPLODED VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 EXPLODED VIEW PARTS LIST . . . . . . . . . . . . . . .

9、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 PACKING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 RadioFans.CN 收音机爱 好者资料库 - 3 - SPECIFICATIONS AM BAND SPECIFICATION Frequency Range CA 530 - 1

10、710 KHz Step 10 KHz EU 531 - 1602 KHz Step 9 KHz FREQ (KHz) UNIT LIMIT 1. Usable sensitivity 999 dBuV = 38 (5mV input) /1000 3. THD (5mV input) 999 % = 36 (ref. to item 8) /600 5. Image Rejection (F+2xIF) 1404 dB = 25 (ref. to item 8) /1400 6. Selectivity 999 dB = 17 (ref. to item 8) /1000 7. Output

11、 999 mV 100 180 (30%, 10mV) /1000 8. Loop sensitivity 20dB S/N 999/1000 dB = 68 603 / 600 dB = 68 1404 / 1400 dB = 68 9. Frequency response 100 - 2.3KHz 999 /1000 dB 0 +/- 6dB (400 Hz, 5mV) FM BAND SPECIFICATION Frequency Range CA/EU 87.5 - 108MHz Step 50 KHz FREQ UNIT LIMIT 1. Usable sensitivity MO

12、NO 98MHz dBu = 72 (60dBu A fi lter) STEREO 98MHz dB = 68 3. THD (60dBu Audio LPF) MONO 98MHz % 0.4 (60dBu Audio LPF) STEREO 98MHz % 80 (refer to item 1) 5. Image Rejection (119.4 MHz) CA&EU 98MHz dB = 70 (refer to item 1) RadioFans.CN 收音机爱 好者资料库 - 4 - 6. Capture ratio (40dBu) dB 60 60dBu 100% mod FM

13、, 30% mod AM 8. Pilot suppression L & R 98 MHz dB 60 9. Frequency response 20Hz & 10KHz dB 0 +/- 1.5 ( 1KHz Ref ) UL 75Us,CE50Us 10. Channel Separation 30 Hz dB = 28 (60dBu IHF wtd) 1 KHz dB = 38 10KHz dB = 28 11. Alternate channel selectivity +/-400KHz, IHF UL dB = 35 CE dB 60 12. Muting level dBu

14、18 +/-6. 13. Output CA 98MHz mV 350600 EU 550900 14. RDS decode sensitivity. dBu = 30 15. Auto-search sensitivity ON dBu = 15 16. Blend ON separation1KHz 98MHz dB 6 +/-2 - 5 - REAR PANEL / FRONT PANEL 1. FM ANTENNA TERMINAL 2. AM ANTENNA TERMINAL 3. OUTPUT (L, R) 4. RS-232 5. IR IN 6. +12V TRIGGER I

15、N 7. AC MAINS INPUT 1. STANDBY LED 2. STANDBY BUTTON 3. FM/AM 4. FM MUTE/MODE 5. BLEND 6. DISPLAY 7. MEMORY 8. PRESET/TUNE 9. REMOTE SENSOR 10. VFD 11. PRESET/TUNE CONTROL KNOB: 1234567891011 FRONT PANEL 1432567 REAR PANEL IMPORTANT NOTES 1. Show the software version Press “DISPLAY” and “FM/AM” . 2.

16、 Light UP all the icon on the VFD Press “FM/AM” & “PRESET/TUNE” . 3. Factory test resets When VFD all Light press any key. 4. AM Step 10K/9K Change When AM band, press “FM MUTE/MODE” & “PRESET/TUNE” . 5. Shipment resets (clear) When pressing “MEMORY” & “PRESET/TUNE” to VFD all Light, press any key.

17、- 6 - 5 4 3 1 2 7 6 6 DISASSEMBLY INSTRUCTIONS 1. Remove machine screws M 4.0 x 6.0 ( 1 to 4 ) from the side panels. Remove tapping screw 3.0 x 8.5 5 from the back panel. Refer to Figure No.1. Figure No.1 2. Pull both sides of the TOP COVER slightly outwards 6 and tilt approx. 35 and then remove in

18、the direction as indicated by the arrow 7 . Refer to Figure No.2. Figure No.2. - 7 - BLOCK DIAGRAM AM LOOP ANT FM ANT OUTPUT FRONT END ENV172D3G1 VFD CPU P89LPC936 U201 U202 VFD DRIVER PT6311 KEY MATRIX Trigger IN U203 EEPROM 24C08 PLLLC72723M RDS DECODER U901 AM/FM IF LA1837 MUTING IR IN U701 74HC8

19、6 STANDBY POWER SUPPLY RS232 M218 REMOTE SENSOR POWER SUPPLY VFD STANDBY 3V3 -VP +5V CPU +10V AC INPUT RELAY L R VT VT cedataclkRDS-CLKRDS-SIGRDS-DATA MPXIN data out (#1)=Power On (#2)=Standby LC7218 U903 ST/MO, MUTE, SMETER TUNE FM OSC/IF AM OSC/IF 1 27 17 16 23 2 30 U902 21 234515 11 15 8 10 IN 16

20、14 20 16 14 22 12/13 5 161924 1918 - 8 - WIRING DIAGRAM TRANSFORMER MAIN board DSP board PSU board LED board KEY board YELLOW BLUE WHITE 7013-0490+0 - 9 - ADJUSTMENT POINTS DIAGRAM OSCRF VT - 10 - FM SIGNAL GENERATOR ANTENNA TERMINAL OUTPUT TERMINAL DISTORTION METER DISTORTION METER AC VOLTMETER OSC

21、ILLOSCOPE AC VOLTMETER OR OSCILLOSCOPE AC VOLTMETER OR OSCILLOSCOPE OUTPUT TERMINAL OUTPUT TERMINAL L R ANTENNA TERMINAL ANTENNA TERMINAL ANTENNA TERMINAL AM LOOP ANTENNA (Accessory) AM LOOP ANTENNA 60cm DIGITAL MILLIVOLT- METER VT_J911 FM SIGNAL GENERATOR AM SIGNAL GENERATOR FM SIGNAL GENERATOR RDS

22、 GENERATOR FM STEREO GENERATOR P901 OUTPUT TERMINAL DC MILLIVOLT- METER UNIT UNIT UNIT UNIT INSTRUMENT SETUP 1. FM MEASUREMENT Fig. 1 Fig. 2 2. RDS MEASUREMENT Fig. 3 3. AM MEASUREMENT Fig. 4 - 11 - ALIGNMENT PROCEDURES FM/RDS SECTION - FM mono: 1kHz, 75kHz devi., 60dB/V - FM stereo: 1kHz, 67.5kHz d

23、evi., 60dB/V Pilot signal 19kHz 7.5kHz devi. OUTPUTS - Connect the 47Kohm resistor unless otherwise noted. ItemStep Connection of instrument FM SG output Stereo modulator output Tuning frequency Output indicator Adjustment point Adjust for Remarks FM IF/RF 1 Fig.1 99.0MHz 1kHz 75kHz devi. 65dBf (60d

24、B) 99.0MHz DC voltmeterL941070mV FM MUTE/MODE switch: ON/AUTO Repeat the steps 1 to 3 until no further adjustment is necessary. 2AC voltmeter IFT on the front end Maximum 3 Distortion analyzer L942Minimum Stereo Distortion Fig.2 99.0MHz Ext. mod. 65dBf (60dB) Channel L or R 1kHz 99.0MHz Distortion a

25、nalyzer IFT on the front end Minimum FM MUTE/MODE switch: ON/AUTO Don t turn more than 180 Stereo Separation Fig.2 99.0MHz Ext. mod. 65dBf (60dB) Channel L or R 1kHz 99.0MHz Oscilloscope R941 Maximum separation Repeat stereo distortion and stereo separation alignment until THD at minimum and separat

26、ion at maximum. Distortion Meter Minimum Mute Level Fig.199.0MHz 18dB99.0MHzOscilloscopeR956 Signal output RDSFig.3 99.0MHz Ext. mod. 65dBf (60dB) RDS 2% MOD 99.0MHz Decode the RDS- Program station AM SECTION AF Modulation: 400Hz, 30% For AH Version Step AM SG output Tuning frequency Output indicato

27、r Adjustment point Adjust for 1530kHz Digital DC voltmeter OSC coil on RF block M971 1.350.2V 2 600kHz 400Hz 30% mod. 60dB/m 600kHz AC voltmeter RF coil on RF block M971 Maximum 3 600kHz 400Hz 30% mod. 60dB/m 990kHz AC voltmeter L972Maximum For C Version Step AM SG output Tuning frequency Output ind

28、icator Adjustment point Adjust for 1 522kHz or 531kHz Digital DC voltmeter OSC coil on RF block M971 1.30.2V (522kHz) 1.350.2V (531kHz) 2 600kHz 400Hz 30% mod. 60dB/m 603kHz AC voltmeter RF coil on RF block M971 Maximum 3 600kHz 400Hz 30% mod. 60dB/m 999kHz AC voltmeter L972Maximum - 12 - POWER SUPP

29、LY BOARD DISPLAY BOARD LED BOARD Top side Top side Top side Bottom side KEY BOARD Top side Bottom side Bottom side Bottom side D209 P/N:1726-042A+000B SECTION:D,ISSUE:B PCB-C426+LED LED-ORANGE KEY-SDBY LED-BLUE GND POWER-ON LED-ORANGE J203B2 M207 P/N:1726-042A+000B SECTION:E,ISSUE:B P/N:PCB-C426+KEY

30、 J201B VR201 C231 C230 STOREFM MUTEFM / AMDISPLAYMODE P/N:1726-042A+000B BLEND SECTION:B,ISSUE:B PCB-C426+DSP KEY-SDBY LED-ORANGE LED-BLUE GND U202 J203A J201A J1 J4 J5 J6 J7 J8 J9 J10 J11 J12 J13 J14 J15 J16 J17 J18 J19 J20 J21 J26 J27 J28 J29 J30 J31 J32 J33 J34 J35 J36 J37 J38 M210 J202A J2 J3 C2

31、02 C201 C212 C213 C211 C210 R222 R221 R220 R219 Q201 R227 R216 R215 J263 R210 R211 J264 R225 D206 J265 J270 J262 R250 R251 J269 M206M204 M203 M202 M201 M205 J261 J266 J267 R252 R261 R262 R263 D210 J268 1 13 14 26 27 39 40 52 AC-IN-L AC-IN-N GND GND POWER-ON +3V3-SDBY P/N:1726-042A+000B SECTION:C,ISS

32、UE:B PCB-C426+PSU WHITEBLUEYELLOW T1AL 250V AT 230V VERSION T1.6AL 250V AT 120V VERSION C103C102 U101 D101 D102 C105 RL101 D106 C106 D105 R103 M103 M104M105 230V 120V M101 M102 D104 D103 D107 D108 R104 C111 C107 C109 R105R106 C110 C101 C104 C116 D109 J101 D301 R301 Q301 J301A C112 T100 L103 L102 R10

33、1 Q302 U116 C100 J103 J105 R108 R102 F101 - 13 - PCB LAYOUT MAIN BOARD Top side 13.5 19.5 U902 8.9V 1 AC3.8V AC3.8V 8V 0V 8V 8.9V 0V OSC IF +B VT GND GND GND ANT M901 U902 8.9V 1 AC3.8V AC3.8V 8V 0V 8V 8.9V 0V M901 U204 U701 U201 +3V3-SDBY POWER-ON GND FM-ST FM-SD FM-ST FM-SD AM-SMETER FM-SMETER DAT

34、A-IN CE-PLL CLK DATA-OUT +5V-D +3V3+3V3 -VP -VP P/N:1726-042A+000B SECTION:A,ISSUE:B PCB-C426+MAIN R-OUT L-OUT M302 TRIG-IN IR-IN M303 C412 C905 C427 L904 M904 L901 U901 M902 R956 R941 R911 L972 L903 U903 R932 L941 L942 L985 P901 M903 R989 L905 0205 R903 R901 R904 R919 R920 R971 R905 R908 R907 R910

35、R909 R928 R929 R915 R973 R921 R922 R923 R947 R948 R974 C968 C941 D902 R931 R942 R943 R975 R954 R959 R960 R957 R958 R944 R950 R961 R953 R952 R918 R949 R951 R927 R924 J907 J909 J911 J912 J913 J915 J916 J917 J923 J924 J929 J904 J931 J932 J933 J936 J939 J219 J946 D980 J945 J245 R984 R981 J944 J942 R964R

36、963 J401B D409 D408 D407 D401 D402 J206 J207 J208 J404 J403 U402 M987 G-O J901 J209 J238 J922 R995 R994 R997 R998 R996 R993 J940 J211 R978 J903 G1 G2 R988 R972 M985 M905 J920 C963 C943 C964 C960 C959 C965 C991 C953 C954 C951 C970 C961 C962 C990C986 C987 C988 C985 C916 C950 C989C992 Q982 C980 Q981 Q9

37、80 Q942 C949 C946 C948 J950 R946 J949 C911 C944 R945 C945 J941 C932 C969 C979 C981 C982 C978 C977 C976 C975 C974 C971 C973 C927 C912 Q922 C913 Q923 C902 C903 C926 C928 C929 Q902 C901 Q901 C904 Q903 C914 C915 C930 C931 C925 C924 Q943 Q944 Q945 C706 D905 R990 Q983 D981 J201 C205 R208 R209 J708 Q984 C2

38、16 C217 C221 U203 C219 C425 C417 C416 C421 C407 C409 Q401 Q403 Q402 C414 C413 C415 C405 C406 C411 C410 C402 C403 C404 C203 R404 R401 J406 D412 D411 R403 R402 J958 J202B C223 C222 J407 C418 D410 J902 J918 J935 J242 J244 D208 R214 R213 J231 J230 R202 J246 J202 R983 J239 J240 R204 R205 J228 J221 J216 J

39、218 J229 J214 J402 J236 R982 J243 R207 R933 J914 C983 C907 C984 J908 J905 D404 D405 D406 J947 J701 J237J925 R955 C996 C995 R916 J210 J409 J405 R236 Z203 R913 J919 J906 R962 J934 J241 C401 C420 C942 M911 Q702 C701 C702R701 R702 R705 C707 J235 C408 R707 R706 R708 R418 D903 C966 J910 R902 J921 GND C999

40、C998 C207 C206 C208 C209 J301B R986 R985 R987 J955 J952 J956 J926 R999 R991 J418 R992 J411 J930 J951 C994 C993 J953 J204 J232 J948 C215 R968 R969 J234 R235 J223 R203 J928 J927 R906 J417 J227 J233 J225 J215 J412 J413 J414 J416 J415 J213 J220 J224 R912 J954 J957 J212 J217 D403 J938 J943 C220 C906 R228

41、 R212 J226 J205 J222 J401 J203 J247 J248 C908 GND1 GND2 GND3 GND4 GND5 J249 J937 R703 R704 C967 C947 C709 J702 D281 R281 C708 C204 C228 C419 C426 L971C L971B L971A C251C250 C253 C254 J256 J255 - 14- MAIN BOARD Bottom side 1 8 9 16 114 1528 1 78 14 1 8 9 16 - 15 - SCHEMATIC DIAGRAM KEY / MCU / DISPLA

42、Y NOTE: 1. RESISTORS ARE CARBON FILM 5% 1/8W UNLESS OTHERWISE SPECIFIED. 2. CERAMIC CAPACITORS ARE 50V 10% UNLESS OTHERWISE SPECIFIED. SHEET: 1 OF 3 TITLE: SIZE: REV: Revision Sheet Size FILE: NATNC426+09CSXX Product Code: Customer NATNC426(A) NAD C426 MCU GND IR-IN GND F1 +3V3-SDBY F2 +5V-D STB CLK

43、 DIN KEY-B KEY-A -VP KEY2-PCB +3V3-SDBY F2 KEY-B LED-G KEY-A -VP LED-R GND GND LED PCB KEY1-PCB F1 IR-IN +5V-D STB CLK DIN FM 106.2 MHz M201 BLEND M204 MODE M203 FM MUTE M202 MEMORY M205 FM/AM M206 MODE J1 J2 J3 J5 J6 J7 J8 J9 J10 J11 J12 J13 J14 J15 J16 J17 J18 J19 J20 J21 J23 J24 J25 J26 J27 J28 J

44、29 J30 J31 J32 J33 J34 J35 J36 J37 J38 M209 VFD C201 100u C202 0.01u 1 2 3 45 6 7 8 U203 24C08 C219 0.1U M210 SENSOR REMOTE D209A GREEN D209B RED M213 TRIGGER_IN 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 J202A D981 1N4148 E B C Q983 C114 R990 1K R991 47K T1 T2 R1 R2 C1+ C1- C2+ C2- GND Vcc V+ V- 12 3 4 5

45、6 7 89 10 11 1213 14 15 16 U204 MAX232 R214 4K7 C216 100u C217 104K 6 7 8 9 1 2 3 4 5 J201 DB9 R209 75R R208 75R C203 223 C205 104K C204 100u 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 J202B C212 100u C213 0.1U C210 100u C211 0.1U R213 4K7 R204 4K7 R203 4K7 R202 4K7 J22 1 P2.0 2 P2.1 3 P0.0 4 1.7 5 P1.6 6

46、P1.5 7 VSS 8 P3.1 9 P3.0 10 P1.4 11 P1.3 12 P1.2 13 P2.2 14 P2.3 28 P2.7 27 P2.6 26 P0.1 25 P0.2 24 P0.3 23 P0.4 22 P0.5 21 VDD 20 P0.6 19 P0.7 17 P1.1 18 P1.0 16 P2.5 15 P2.4 U201 P89LCP936 C223 100u C222 104K R215 470R R216 470R R219 680R R220 820R R221 1K8 R222 680R 49 LED2 50 LED1 51 GND 52 OSC

47、32 GR18 31 SG17 30 SG16 29 SG15 28 SG14 27 SG13 26 SG12 25 SG11 24 SG10 23 SG9 22 SG8 21 SG7 20 SG6 19 SG5 18 SG4 17 SG3 33 VDD 34 VEE 35 GR10 36 GR9 37 GR8 38 GR7 39 GR6 40 GR5 41 GR4 42 GR3 43 GR2 44 GR1 45 VDD 46 LED5 47 LED4 48 LED3 16 SG2 15 SG1 14 VDD 13 K4 12 K3 11 K2 10 K1 9 STB 8 CLK 7 NC 6

48、 DIN 5 DOUT 4 SW4 3 SW3 2 SW2 1 SW1 U202 PT6311R225 10K R227 56K R999 5K1 R212470R R228 470R L201 100uH 203 5V6 R235 4K7 R236 4K7 VR201 J201B J201A E B C Q702 2SC1923 R704 1K R705 10K R701 1K5 C709 100u C706 104K C701 473J R703 30K R702 330R 1606 IR_IN 1 1A 2 1B 3 1Y 4 2A 5 2B 6 2Y 7 GND 14 VDD 13 4

49、B 12 4A 11 4Y 10 3B 9 3A 8 3Y U701 74HC86 D701 DAP202K C702 10u R706 15K D903 3V3 C206 104K C207 104K C208 104K C209 104K D208 SR2100 R288 100R D210 1N4148 R229 0R J301B M207POWER ON R252 820R 1 2 3 4 1 2 3 4 J203A 1 2 3 4 1 2 3 4 J203B R211 120R R250 4K7 R210 100R IN GND OUT U3 LM1117-3V3 E C B Q201 DTC114 SG18 SG17 SG16 SG15 SG14 SG13 SG12 SG11 SG10 SG09 SG08 SG07 SG06 SG05 SG04 SG03 SG02 SG01 SG17 SG16 SG15 SG14 SG13 SG12 SG11 SG10 SG09 SG08 SG07 SG06 SG05 SG04 SG03 SG02 SG01 +3V3-SDBY POWER-ON GND GND GND GND GND GND GND GND GND GND GND GND