NAD-C425-tun-sm 电路图 维修手册.pdf

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1、NAD C 425 STEREO AM/FM TUNER C 425 STEREO AM/FM TUNER SERVICE MANUAL RadioFans.CN 收音机爱 好者资料库 - 2 - 3 - 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

2、acceptably 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 REAR PANEL / FRONT PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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

5、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 ADJUSTMENT POINTS DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 INSTRUMENT SETUP . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6、. . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 ALIGNMENT PROCEDURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 PCB LAYOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7、. . . . . . . 11-12 SCHEMATIC DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-14 IC BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-18 ELECTRICAL PARTS LIST

8、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-27 EXPLODED VIEW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 EXPLODED VIEW PARTS LIST. . . . . . . . . . . . . . . . .

9、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29-30 PACKING DIAGRAM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 RadioFans.CN 收音机爱 好者资料库 - 2 - 3 - SPECIFICATIONS AM TUNER SECTION Input level is expressed as the read

10、ing in open-circuit of 75-ohm source impedance signal generator Usable Sensitivity (999/1000kHz) 30dB S/N Ratio (5mV in) 38dB THD (5mV in) 3% IF Rejection (450kHz) 36dB Image Rejection (F+2xIF) 28dB Selectivity 17dB Output 130 +/-20mV Loop Sensitivity (20dB S/N) 999/1000 kHz 66 dB 603/600 kHz 66 dB

11、1404/1400 kHz 66 dB Frequency response (100 - 2.3 kHz, 5mV) 6 dB FM TUNER SECTION *C *AH Input level is expressed as the reading in open-circuit of 75-ohm source impedance signal generator Usable Sensitivity (98 MHz) 13 dB 13 dB Signal / Noise Ratio Mono 72 dB 72 dB (60 dB, IHF wtd) Stereo 66 dB 66

12、dB Frequency Response (20 Hz - 15 kHz, 60 dB) 01.0 dB 01.0 dB Channel Separation (60 dB) 30 Hz 33 dB 33 dB 1 kHz 42 dB 42 dB 10 kHz 32 dB 32 dB Alternate Channel Sensitivity (40 dB, 400 kHz) 60 dB 45 dB Capture Ratio (40 dB) 3 dB 3 dB AM Suppression (60 dB, 100% Mod.FM, 30% Mod AM) 65 dB 65 dB Image

13、 Rejection (119.4 MHz) 85 dB 85 dB I.F. Rejection (10.7 MHz) 78 dB 78 dB Pilot Suppression (60 dB) 60 dB 60 dB THD (60 dB, L=R 75 kHz for AH, 40 kHz Dev for C) Mono 0.25% 0.25% Stereo 0.35% 0.35% Auto-Search sensitivity On 24 dB 24 dB Off 15 dB 15 dB RDS Decode Sensitivity 26 dB 26 dB PHYSICAL SPECI

14、FICATIONS Dimensions (Width x Height x Depth) 435 x 80 x 285 mm Net weight 4 kg (8.8 lbs) Shipping weight 5.1 kg (11.22 lbs) RadioFans.CN 收音机爱 好者资料库 - 4 - 5 - REAR PANEL / FRONT PANEL 1. FM ANTENNA 2. AM ANTENNA 3. OUTPUT 4. IR IN 5. 12V TRIGGER IN 6. AC LINE CORD 7. RS-232 1. POWER ON / OFF 2. POWE

15、R STATUS INDICATOR 3. BLEND 4. MEMORY 5. FM MUTE / MODE 6. AM / FM 7. DISPLAY 8. PRESET / TUNE 9. DISPLAY AREA 10. PRESET / TUNE CONTROL FRONT PANEL REAR PANEL IMPORTANT NOTES 1. Show the software version Press “BLEND” and “AM/FM”. 2. Light UP all the icon on the VFD Press “BLEND” & “DISPLAY”. 3. Fa

16、ctory test resets When VFD all Light press any key. 4. AM Step 10K/9K Change When AM band, press “AM/FM” & “PRESET/TUNE”. 5. Shipment resets When pressing “DISPLAY” & “PRESET/TUNE” to VFD all Light, press any key. - 4 - 5 - 5 4 3 1 2 7 6 6 DISASSEMBLY INSTRUCTIONS 1. Remove machine screws M 4.0 x 6.

17、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 the direction as indicated by the arrow 7 . Refer to Figure No.2. Figure No.2. - 6

18、 - 7 - AM LOOP ANTFM ANTOUTPUT FRONT END ENV172D3G1 VFD CPU LC866448B U201 U202 VFD DRIVER PT6311 KEY MATRIX Trigger IN U203 EEPROM 24C08 PLLLC72723M RDS DECODER U901 AM/FM IF LA1837 MUTING IR IN U701 74HC86 M218 REMOTE SENSOR POWER SUPPLY VFD -VP +5V CPU +10V AC INPUT L R VT VT cedataclkRDS-CLKRDS-

19、SIGRDS-DATA MPXIN data out (#1)=Power On (#1)+(#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 1614 20 16 14 22 12/13 5 161924 1918 BLOCK DIAGRAM - 6 - 7 - WIRING DIAGRAM MAIN BOARD KEY BOARD DISPLAY BOARD LED BOARD TRANSFORMER POW

20、ER SUPPLY BOARD YELLOW BLUE WHITE - 8 - 9 - ADJUSTMENT POINTS DIAGRAM OSCRF VT - 8 - 9 - FM SIGNAL GENERATOR ANTENNA TERMINAL OUTPUT TERMINAL DISTORTION METER DISTORTION METER AC VOLTMETER OSCILLOSCOPE AC VOLTMETER OR OSCILLOSCOPE AC VOLTMETER OR OSCILLOSCOPE OUTPUT TERMINAL OUTPUT TERMINAL L R ANTE

21、NNA 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 GENERATOR FM STEREO GENERATOR P901 OUTPUT TERMINAL DC MILLIVOLT- METER UNIT UNIT UNIT UNIT INSTRUMENT SETUP

22、 1. FM MEASUREMENT Fig. 1 Fig. 2 2. RDS MEASUREMENT Fig. 3 3. AM MEASUREMENT Fig. 4 - 10 - ALIGNMENT PROCEDURES FM/RDS SECTION - FM mono: 1kHz, 75kHz devi., 60dB/V - FM stereo: 1kHz, 67.5kHz devi., 60dB/V Pilot signal 19kHz 7.5kHz devi. OUTPUTS - Connect the 47Kohm resistor unless otherwise noted. I

23、temStep 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 (60dB) 99.0MHz DC voltmeterL941070mV FM MUTE/MODE switch: ON/AUTO Repeat the steps 1 to 3 until no further adjus

24、tment 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 analyzer IFT on the front end Minimum FM MUTE/MODE switch: ON/AUTO Dont turn more than 180 Stereo Separation

25、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 separation at maximum. Distortion Meter Minimum Mute Level Fig.199.0MHz 18dB99.0MHzOscilloscopeR956 Signal output RD

26、SFig.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 indicator Adjustment point Adjust for 1530kHz Digital DC voltmeter OSC coil on RF block M971 1.350.2V 2 600kHz 400Hz

27、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 indicator Adjustment point Adjust for 1 522kHz or 531kHz Digital DC voltmeter OSC coil on RF block M971 1.30.2V

28、(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 - 11 - PCB LAYOUT POWER SUPPLY BOARD DISPLAY BOARD LED BOARDKEY BOARD - 12 - 13 - MAIN BOARD - 12 - 13 - SCHEMATIC DIAGRAM KEY

29、 / MCU / DISPLAY NOTE: 1. RESISTORS ARE CARBON FILM 5% 1/8W UNLESS OTHERWISE SPECIFIED. 2. CERAMIC CAPACITORS ARE 50V 10% UNLESS OTHERWISE SPECIFIED. 425KB-MP.sch-1 - Tue Jul 18 09:17:14 2006 6.5V - 14 - TUNER NOTE: 1. RESISTORS ARE CARBON FILM 5% 1/8W UNLESS OTHERWISE SPECIFIED. 2. CERAMIC CAPACITO

30、RS ARE 50V 10% UNLESS OTHERWISE SPECIFIED. - 15 - Serial Data Interface DIN DOUT CLK STB VDD R OSC SW1 SW2 SW3 SW4 LED1 LED2 LED3 LED4 LED5 K1 K2 K3 K4VDDGNDVEE SG1/KS1 OSC General Input Register LED Driver Dimming Circuit Grid Driver Segment Driver Grid Driver Key Scan Output Control Dispaly Memory

31、 Timing Generator Key Matrix Memory SG2/KS2 SG3/KS3 SG4/KS4 SG5/KS5 SG6/KS6 SG7/KS7 SG8/KS8 SG9/KS9 SG10/KS10 SG11/KS11 SG12/KS12 SG13/GR16 SG14/GR15 SG15/GR14 SG16/GR13 SG17/GR12 SG18/GR11 SG19/GR10 SG20/GR9 GR1 GR2 GR3 GR4 GR5 GR6 GR7 GR8 IC BLOCK DIAGRAM Display Board U202: PT6311 - 16 - 17 - Mai

32、n Board U201: P89LCP936 ACCELERATED 2-CLOCK 80C51 CPU 4 kb/8 kB/16 kB CODE FLASH 256-BYTE DATA RAM PORT 2 CONFIGURABLE I/Os PORT 1 CONFIGURABLE I/Os PORT 0 CONFIGURABLE I/Os KEYPAD INTERRUPT PROGRAMMABLE OSCILLATOR DIVIDER CPU clock CONFIGURABLE OSCILLATOR ON-CHIP RC OSCILLATOR internal bus CRYSTAL

33、OR RESONATOR POWER MONITOR (POWER-ON RESET, BROWNOUT RESET) UART ANALOG COMPARATORS 512-BYTE AUXILIARY RAM I2C-BUS 512-BYTE DATA EEPROM (P89LPC935/936) PORT 3 CONFIGURABLE I/Os CCU (CAPTURE/ COMPARE UNIT) (P89LPC935/936) P89LPC933/934/935/936 WATCHDOG TIMER AND OSCILLATOR TIMER 0 TIMER 1 REAL-TIME C

34、LOCK/ SYSTEM TIMER SPI ADC1/DAC1 ADC0/DAC0 (P89LPC935/936) P31:0 P27:0 P17:0 P07:0 X2 X1 TXD RXD SCL SDA T0 T1 CMP2 CIN2B CIN2A CMP1 CIN1A CIN1B OCA OCB OCC OCD ICA AD10 AD11 AD12 AD13 DAC1 AD00 AD01 AD02 AD03 DAC1 ICB SPICLK MOSI MISO SS P89LPC935FDH P89LPC936FDH 1 2 3 4 5 6 7 8 9 10 11 12 13 14 16

35、 15 18 17 20 19 22 21 24 23 26 25 28 27 P2.0/ICB/DAC0/AD03 P2.1/OCD/AD02 P0.0/CMP2/KBI0/AD01 P1.7/OCC/AD00 P1.6/OCB P1.5/RST VSS P3.1/XTAL1 P3.0/XTAL2/CLKOUT P1.4/INT1 P1.3/INT0/SDA P1.2/T0/SCL P2.2/MOSI P2.3/MISO P2.7/ICA P2.6/OCA P0.1/CIN2B/KBI1/AD10 P0.2/CIN2A/KBI2/AD11 P0.3/CIN1B/KBI3/AD12 P0.4/

36、CIN1A/KBI4/DAC1/AD13 P0.5/CMPREF/KBI5 VDD P0.6/CMP1/KBI6 P0.7/T1/KBI7 P1.0/TXD P1.1/RXD P2.5/SPICLK P2.4/SS - 16 - 17 - VCC 8 7 4 6 5 3 2 1 GND WP SCL LOAD LOADINC DATA WORD ADDR/COUNTER Y DEC X DEC R/W COMP SERIAL CONTROL LOGIC EN H.V. PUMP/TIMING DATA RECOVERY EEPROM SERIAL MUX DOUT/ACK LOGIC DEVI

37、CE ADDRESS COMPARATOR START STOP LOGIC SDA A2 A1 A0 DIN DOUT Main Board U203: AT24C08A-10PU Main Board U204: MAX232D 16 15 14 13 12 11 10 9 1 2 3 4 5 6 7 8 VCC GND T1OUT R1INC2+ C1- V+ C1+ R1OUT T1IN T2IN R2OUTR2IN T2OUT V- C2- Main Board U402: NJM78M56FA 1? INPUT 3? OUTPUT 2? GND Main Board U701: 7

38、4HC86 1 2 3 4 5 6 7 14 13 12 11 10 9 8 1A 1B 1Y 2A 2B 2Y GND VCC 4B 4A 4Y 3B 3A 3Y 123456789101112131415 302928272625242322212019181716 ALC AM OSC AM MIX AM RF.AMP REG AGC AM IF AM S-METER TUNING DRIVE STEREO DRIVE VCC VCC AM/FM IF-BUFF FM S-METER S-CURVE AM IF FM DET GND FM IF INPUT AM MIXER OUTPUT

39、 FM IF INPUT BYPASS AM IF INPUT GND TU-LED ST LED AM-IF OUTPUT FM DETECTOR AM NARROW CF FM S-METER OUTPUT AM S-METER OUTPUT MUTE FM/AM SWITCH PILOT VCO SD COMP DET BUFF DECODER ANTI-BIRIDE 3 rd 5 th STEREO SW MUTE VCO 304kHz FF 38k P-DET FM SD ADJ OSC REG AM RF INPUT AFC AM AGC AM DETECTOR INPUT FM

40、DETECTOR OUTPUT MPX IUTPUT MPX OUTPUT MPX OUTPUT AM STEREO L INPUT AM STEREO R INPUT L-OUT R-OUT FF 19k FF 19k PILOT DET Main Board U901: LA1837L-E - 18 - 19 - Main Board U902: LC72723M Vdda 3 REFERENCE VOLTAGE ANTIALIASING FILTER DATA DECODER VREF 1 VREF FLOUT 5 CIN 6 PLL (57kHz) CLOCK RECOVERY (11

41、87.5Hz) + _ 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 XIN 8 XOUT RDS-ID DETECT RAM (128bits) 21 22 16 15 20 23 871714131211109 5 4 3 2 18 19 24 1 6 XIN FMIN AMIN CE DI CL D0 OUT0OUT1 XOUT PHASE DETEC

42、TOR CHARGE PUMP REFERENCE DIVIDER SWALLOW COUNTER 1/16, 1/17 4 BIT SHIFT REGISTER LATCH UNIVERSAL COUNTER 1 2 12-BIT PROGRAMMABLE DIVIDER SYC OUT2 OUT3OUT4 OUT5 OUT6IN0IN1 VSS VDD LCTR HCTR PD2 PD1 Main Board U903: LC7218-E - 18 - 19 - ELECTRICAL PARTS LIST DISPLAY ASSY PC BOARD PCB-C42526+DSPPCB AS

43、SY DISPLAY PCB 1725-859A+0000PCB MAIN/KEY/DIS/PSU/LED CAPACITOR C201157B-107M+K-LIICE 6.3V 100UF 20% RLT C202150F-103K+2-FCCC 50V 0.01uF 10% AT 3.5 C210150F-104K+2-FCCC 50V 0.1UF 10% AT C211157Q-107M+K-LUICE 35V 100UF 20% RLT C212157B-107M+K-LIICE 6.3V 100UF 20% RLT C213150F-104K+2-FCCC 50V 0.1UF 10

44、% AT DIODE D201, D2064804-1480+CDIODE 1N4148M-A(WA) ATS WAFER/CONNECTOR J202A2101-1441+0FLEXIBLE CONN 15P P1.0 R J203A2102-031R+004WAFER 3P P2.5 RIGHT TRANSISTOR Q201, Q202485C-114E+KTR DTC114ES RLT RESISTOR R210, R2114701-221J+2RCF 1/8W 220R 5% AT R215, R2164701-471J+2RCF 1/8W 470R 5% AT R2194701-6

45、81J+2RCF 1/8W 680R 5% AT R2204701-821J+2RCF 1/8W 820R 5% AT R2214701-182J+2RCF 1/8W 1.8K 5% AT R2224701-681J+2RCF 1/8W 680R 5% AT R2274701-563J+2RCF 1/8W 56K 5% AT IC U2023131-8700+0IC PT6311(L) VFD DRIVER SWITCH M201, M202, M203, M204, M205, M2065200-3538+0SWITCH, TACT SKHHBY 7MM LocationPart NumberDescription - 20 - 21 - LocationPart NumberDescription WIRE J201A7012-6688+0CONN W