Nikko-Fam450-tun-sm维修电路原理图.pdf

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1、 RadioFans.CN 收音机爱 好者资料库 (., CONTENTS 1. SPECIFICATION I. 2. EXTERNAL VIEW 2. 3. INTERNAL VIEW 3. 4. PARTIAL DISASSEMBLY. 3-5. 5. DIAL MECHANISM . . 5. 6. MEASUREMENT AND ADJUSTMENT 6-A, 7. PRINTED CIRCUIT BOARD ftE 8. 9. 10. TUNER PCBASSY 9. BLOCK DIAGRAM IO. OVERALL DIAGRAM I I. PARTIAL CHANGES MA

2、DE ACCORDINGDESTINATION. 12. PARTS LIST. t3-* t5. SEM ICONDUCTOR SPECI FICATION TRANSISTOR COMPLEMENT. . 16. FIELD EFFECT TRANSISTOR COMPLEMENT . . 16. RECTIFIER-DIODE, ZENER-DIODECOMPLEMENT. . I6. INTEGRATEDCIRCUITCoMPLEMENT. .17_19. 11. 12. !-. t- L r L RadioFans.CN 收音机爱 好者资料库 SPECIFICATION 1. FM

3、TUNER SECTION Sensitivity Ouiting Slope Selectivity lmage Rejection lF Rejection Signal to Noise Ratio Capture Ratio Muting Sensitivity Distortion Distortion Stereo Separation Output Voltage De-Emphasis 2. AM TUNER SECTION Sensitivity Selectivity lmage Rejection lF Rejection Distortion Signal to Noi

4、se Ratio Output Voltage (IHF) (s/N 50dB) (lHF) (98MHz) (98MHz) (lHF) (MONO) (STEREO) (1KHz) (SOpSec) 10KHz (tHF) (lHF)110KHz . . . (1000KH2) (1000KH2) !2dB NOMINAL 2ttY 4.51tY 55dB 45dB 70dB 65dB 1.6dB 12dB o.20/o O.5o/o 42dB 690mV -10.37dB 300pV/m 35dB 45dB 35dB 17o 45dB 135mV LIMIT 3pV 1OpV 35dB 4

5、0dB 60dB 60dB 3dB rSdB O.5o/o 1o/o 3sdB r3dB c 1000prV/m 30dB 40dB 30dB 2Vo 40dB 12dB t o RadioFans.CN 收音机爱 好者资料库 EXTERNAL VIEW FRONT PANEL I v v (1) Signal/Tuning meter (2) Dial pointer (3) Stereo indicator (4) Power switch (5) Tuning knob . (6) Hi-blend switch (7) FM muting switch (8) Selector swi

6、tch REAR PANEL IJ (1) (2t (3) (4) (5) Coaxial cahle holder (GND) 7 5 ohm FM antenna terminal 300 ohm FM antenna terminal Ground terminal AM antenna terminal (6) AM bar antenna (7) AC supply cord (8) AC 22Ol24O selector switch (9) Output terminal l 2. RadioFans.CN 收音机爱 好者资料库 r- INTERNAL VIEW TOP VIEW

7、 Selector switch Fly wheel Power switch Tuner PCB assy board Power transformer AC cord AM bar antenna Antenna terminals t_ (1) (2t (3) (4t (5) (6) (71 (8) (1) (2t (3) (41 (5) BOTTOM VI EW Power switch Signal/Tuning meter Fly wheel Tuner PCB assy board AM bar antenna cJ PARTIAL DISASSEMBLY CABINET RE

8、MOVAL PHoro-l PHOTO_2 Stand the cabinet up and remove screws (1-4) as shown in Photo-1. Return the cabinet to its original position and pull forward and then lift upto remove it (Photo-2). BOTTOM PLATE REMOVAL Turn the cabinet and remove screws (1-9) as shown in Photo-3. r PHOTO_1 PHOTO-3 3. RadioFa

9、ns.CN 收音机爱 好者资料库 ,YJ .ll.- v z FRONT PANEL REMOVAL PHOTO-4 Remove screws (1-2) and nut (3) as shown in Photo 4-5. TUNER PCB ASSY BOARD REMOVAL PHOTO_6 Remove screws (1-8) as shown in Photo 6 then lift the circuit board up to remove it. SWITCH PCB ASSY REMOVAL Remove screws (1-2) forward to remove it

10、. PHOTO-8 as shown in Photo 8 and pull PHOTO_5 POWER TRANSFORMER REMOVAL PHOTO-7 Remove screws (1-2) as shown in Photo 7 then lift the transformer up to remove it. FLY WHEEL REMOVAL PHOTO-9 Remove screws (1-4) as shown in Photo 9 and pull forward to remove it. r I I 4. RadioFans.CN 收音机爱 好者资料库 POWER

11、SWITCH REMOVAL PHOTO-10 Remove screws (1-21 as shown in Photo 10 and pull forward to remove it. DIAL MECHANISM METER REMOVAL PHOTO-1 1 Remove screws (1-4) as shown Photo 11 and pull forward to remove it. It vJ 5 I .,L r- U RadioFans.CN 收音机爱 好者资料库 MEASUREMENT AND ADJUSTMENT Set the tuning dial pointe

12、r to zero(0) position on the dial panel. . lf the dial pointer fails to coincide with the zero(0) position at the left end of the knob rotation, have it reset to zero(O) Q! oosition by sliding on the dial string and then proceed as follows. FM SECTION 1. FREOUENCY COVERAGE AND TRACKING ADJUSTMENT Fo

13、r connecting, reler to Fig. 1. For adjusting point. refer to Fig. 2. StepGenerator and Dial Freq. Adjustlndication and Remarks 1 88 MHzL104 Oscillator coil core Adjust for max. reading 2108 MHz c111 Oscillator Trimmer Adjust for max. reading 388 MHzL101ANT coil core, RF coil core 4108 MHzFM1 Adjust

14、for max. reading 588 MHzL102ANT coil core, RF coil core b 108 MHzFM2 Adjust for max. reading 7 Repeat step 1, 2,3, 4,5, 6 Align after complete tuning STANDARD DUMMY ANTENNA FAM-450 TO FM ANTENN TERMINALS OSCILLO SCOPE lo ol l-zfi, I L,rrraar-l Ltlllrlrrll L,rr rralrrra- I llatltllrtr I ltttrlatrtttf

15、l I I lttrlrrfl I e lttlltrltrl I o 4ttgtltult I ol_ !17 _i to (9l - =:- - a-il C o a ;aa_. OOeoO OFF ooo c- _e-_c . c E -r#;* tt oo e STANDARD SIGNAL GENERATOR Fig. 1 Shield cable DISTORTION METER 6. RadioFans.CN 收音机爱 好者资料库 ta a) 2. Fig.2 FM-IF STAGE ADJUSTMENT For adjustment of the discriminator c

16、oil T2O1 , connect the testing instruments as shown in Fig. 1 and then proceed as follows: (1) With no RF signal applied to the receiver, adjust the lower core of T201 until the pointer of the tuning meter on the receiver indicates the center position of the meter scale. (2) Apply RF signal to the r

17、eceiver and adjust the tuning knob so that the tuning meter indicates the center posi- tion. (3) Under this condition, adjust the upper core of r2o1 for minimum distortion. (4) Repeat the above steps (1)through (3) two or three times so that the distortion factor is most improved. Note: For adjustin

18、g point, refer to Fig. 2. FM SEPARATION ADJUSTMENT with stereo-modulated RF signal applied to the receiver, make adjustment as follows: (1) Turn the semi-fixed resistor R415 (150K ohm) fully clockwise. (2) Connect a frequency counter to the test point #1 5 on the Tuner PCB Assy Board. Adjust the sem

19、i-fixed resistor R405 (10K ohm) for the frequency of 19 KHz t 19 Hz. (3) Adjust the semi-f ixed resistor R415 (150K ohm) for maximum stereo separation. Note: For adjusting point. refer to Fig. 2. 3. t) o l I I17. I I- Ftu- AM2 FM2 AMl FM1 RadioFans.CN 收音机爱 好者资料库 AM SECTION 1. FREOUENCV COVERAGE AND

20、TRACKING ADJUSTMENT The following is intended to described the procedure of adjusting the AM section of the receiver using a sweep generator. ln the adjustment, the output voltage is applied through inductive coupling. For adjustment. place a loop antenna near the receiver under test and ovserve the

21、 waveform of detector output (at the point lf22 on the Tuner PCB Assy Board)displayed on the alignment oscilloscope. For adjustment point, refer to Fig. 2. The waveform disprayed on the arigment oscilloscope is as shown in Fig. Fig.3. Step Generator and Dial Freq. Adjust lndication and Remarks 1 52O

22、 KHz T301 Oscillator coil core adjust for maximum reading 21650 KHz AM2 Oscillator trimmer adjust for maximum reading 3600 KHz AM BAR ANT. Antenna coil adjust for maximum reading 41400 KHz AMl Antenna trimmer adjust for maximum readinq 5 Repeat steps 1-4 to obtain best tracking 2. AM-IF STA.GE ADJUS

23、TMENT This adjustment is similar to the frequency coverage and tracking adjustment. Switch the sweep generator from RF to lF and follow the procedure below. The adjusting procedure is as follows: (1) With the receiver set to a high receiving frequency (variable capacitor in full open position), adju

24、st T302 and T303 until the lF waveforem becomes maximum. (21 lf , in this case, the adjustment is difficult because of disturbing sighal, facilitate the adjustment. (3) The waveform displayed on the aligment oscilloscope is as shown in Fig. 4. For adjusting posint, refer to Fig. 2. the variable capa

25、citor may be turned to 520KHZ MARKER SIGNAL 1,650KH2 MARKER SIGNAL 600KHZ 1400KHZ MABKER MARKER SIGNAL SIGNAL Fis. 3 Fig.4 8. RadioFans.CN 收音机爱 好者资料库 BLOCK DIAGRAM MODEL FAM.4sO EXT. AM ANT. FRONT ENDCERAMIC FILTER cF101 CF103 EXT. AM ANT. AM TUNER SELECTOF SWITCH AM BAR ANT. AC LINE POWER TRANSFORM

26、ER to. RadioFans.CN 收音机爱 好者资料库 .f,- (, Dtsc colL 0 a n i SIG./TUNING METER OUT PUT POWER SUPPLY l L I .rit# LT STAB. I I t i i i 1 t-. :, i i FM IF AMP. 1B HI.BLEND SW. RadioFans.CN 收音机爱 好者资料库 OVERALL DIAGRAM MOD PCa orol 28K49 1103 1027 -t lir cl04 7Pf,PO R 101 17 RF COIL Ll02 10t8 ur.ArArcEl-rq -

27、- I I sooq I |-_BALANCE I -Jld Ll 05 cF1 01,CFt 03 SFE O.7MA8 3.3K R 103 2.2t,H . irbi 68 , R4O1 22K r- _T_ lcBN 4K cl .! AM AilT coII LI c30a .o1 l+ 4 t- # d o POWER SW wHr BLX WHT YEL WL 3ilfl ffiilb r+ lllo FilE ,:t.;. cl.oo47 DC5KV) q G ac 120v l , L- t- L-r YEt PT r-r -253 fd 6A. CANADA ac 220v

28、 ie- / eloa 1i 9: L1o4 c 2SC 4 4 o 4 rc 301 HAI t 9? C9O3 22OM,/16 O9O1 2SO23S = n o t- lo I lo I lo I 9 x tol _:_l ; -t I I s4 Y Y mD, Ilt cl .o1 Ac125v I j F3 1A il. RadioFans.CN 收音机爱 好者资料库 DIAGRAM MODEL FAM-45O R2O5 12K T103 1027 rl l- -Jl d cFl 01,CF1 03 SFE 1 O,7MA8 L105 2.2ilX s2 ooN ffiJ, _ l

29、lurlle otr o lqr |, dJ I lL I l 717 $E l.i th o _ ji_ I r .oors c423 BF3O2 t3axHz) o 2 DE-EMPHASIS t5,o.oorzlft) 50,. 680P L-l YEI PT T 1-253 td SA CANADA oP l: o c oi G Ft ot ol 8nt fl aF3or c41-6-.OO1 (38KHz) F415 tsoK(a) R4OA 6.ar 33x I - ncrc lnlto 1rK c11o1ou/16 : I L : lr.1 - jr iu*u*: =ef rr+

30、J-s t .+ + + c422 +l f c415 0o1 0 cltz-.oor lll -rffiFf i6lnnnn. R41?.4.3K lnrrsr.rrl 1l . ltRa23- rx -t o EJ.- ol -*t- -t I SIGtrAL/TUtrI TG M ETI tt. RadioFans.CN 收音机爱 好者资料库 TypeClass ot Service Maximum Ratings (TA=25oC)Electrical Characteristics Typical Valuel TA=2soc Power Supply (v) Power Dissi

31、ptation Pd. (MWI Operating Temp. Range Topt ct Storage Temp. Range Tstg c Signal to Noise Ratio I nput=74dBp Mod.=30% (dB) Distortion lnput=74d8, Mod.=30% t%) Detector Output I nput=74dBp Mod.=30% (mV) AGC. FOM I nput: loodBrr=odB Consumption Vcc=1 2V lmA) Manulacture HAl 197AIV RADIO15 450 -20-+70-

32、55-+125 530.42127514.5HITACHI I NTEGATED CI RCUIT COMPLEMENT SPECI FICATION CONNECTION DIAGRAM (TOP VIEW SCHEMATIC DIAGRAM l) o G 17. RadioFans.CN 收音机爱 好者资料库 U INTEGRATED CIRCUIT COMPLEMENT GoNNECTTON DTAGRAM (TOP VIEW) -(t Mtrimum fl6rino Ta=25C Elocrrical Ch.acrsisaica (Typicrl v.l) Ta = 25c Oi3si

33、paion Otsrating c Stor.gt T3tg rc) Limntino t*) Signri ro d8)da HAI l37W FM.IF OuaJhrur-D.l.clorl4550t9 -20- +80-55- + I 25 32 l5 -3dB oohtl 3molMrN.5745HITACHI SCHEMATIC DIAGRAM i,. - Ui r8. RadioFans.CN 收音机爱 好者资料库 - INTEGRATED CI RCU IT COMPLEMENT SPECI F ICATION CONNECTION DIAGRAM (TOP VIEW) INDE

34、X SCHEMATIC DIAGRAM , ; -.:-. v/ -a I I I I tt t: bgr I I I I I I rypeClass of Seruice Maximum Ratings (TA=25C)Electrical Characteristics Tvpical Value) TA=25oC Manufacture Supply v) Power Dissipation Pd. (mwl Lamp Driver l1 (mA) Operating Temp. Range Topt (c) Storage Temp. Range Tstg (c) lnput lmpedance Zin (KC,) Stereo Separation dB) Channel Balance (dB) Distortion (stereo) l/.t Lamp Level mV) Output Voltage lnput =2-mV (mV) HA1 196 FM STEREO DEMODULATOR 15490 -20 - +70-55 - +125 75 50 (at 1 KHz) tl.5 0.1 (at 1 KHz) MtN 4.O1.2VH ITACH I r9. I -J RadioFans.CN 收音机爱 好者资料库