Kenwood-KX747R-tape-sm 电路图 维修手册.pdf

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1、AUTO BEVERSE STEREO CASSETTE DECK Hadio en TolnviimiBrvlee KEES van de MORTEL Boksheuvelstraat 14 5222 AN s-HERTOGENBOSCH Tel.: (073)6218344 Knob (Eject) (K29-1643-04 Cassette lid assy (A53- Knob (Button) (K29-1638-04) x3 Knob K29-1642-04) Slide switch (S31-2062-15) x2 Knob (Button) (K27-1226-04) Fo

2、ot (J02-0126-05) x2 Knob assy (K29-1728-04) x2 Knob (Button) Knob (K29-1639-04) x4 (K29-1641-04) x2 Phone jack (3P) (E11-0104-15) -LINE IN-LINE OUT REC PLAY H S Phono jacl (4P) (E13-0497-05) Power cord bushing* (J42-0083-05) AC power cord (E30-) *Refer to parts list on page 15. RadioFans.CN 收音机爱 好者资

3、料库 KX-747R DISASSEMBLY FOR REPAIR 1. Remove the screw of the fitting for REC BALANCE and REC LEVEL dials from the bottom plate side. 2. Pull the fitting to this side in the state where the board is attached to it (zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA O ). 3. Remove two screws of the

4、tape counter board and re- move the board ( Q , Q ). 4. Five screws of the board to which the level meter is mounted can now be removed, and the board can be removed to this side. ( , ). 2 RadioFans.CN 收音机爱 好者资料库 mm VUVUOViazyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA 13A31 )l30ig RadioFans.

5、CN 收音机爱 好者资料库 KK-747R CIRCUIT DESCRIPTION Functions of active elements REC/ PLAY (X28- 1640- 12) Components Application/ f u nction Operation/conditions I C 1 Playback equalizer amplifier The gain at 315Hz is approx. 50dB. iC2 Recording equalizer amplifier (incorporating equalizer select switch for

6、CrOi, metal) The reference power supply is fitted externally because of use with single power supply. (Terminal No. 8) IC3 IC4 Reel motor drive Assist motor drive IC5 Headphone amplifier IC6,IC7 Level meter drive IC8 ;u-COM (mechanism control) IC9 ;LI-COM (counter control) IC10 3-terminal regulator

7、(+ 20V) Q1Q4 Head select switch OFF in REC, REC PAUSE mode, and ON in other modes. High withtstand voltage, suitably low saturation voltage and small ON resistance are required. Compatible article is 2SC1841 other than those in parts list. 05,06 Head select switch ON in REC, REC PAUSE mode, and OFF

8、in other modes. (IVIutually supple- mentary to Q104). Use transistors same as those of Q1 Q4 in the same set. (It is because the shocl noise at the time of head selection is caused by the difference in the saturation voltage between Q1 Q4 and Q5,06.) Q7,Q8 Playback equalizer select switch OFF when n

9、ormal tape (120MS) is used and is ON when CrOj, metal tape (120MS) is used. 09,010 PLAY mute switch O N in REC, REC PAUSE mode, and the output of the playback equalizer is muted so that no bias leaks into the PLAY input terminal of the Dolby unit. 013,014 REC mute switch OFF in REC mode, and ON in o

10、ther modes (including REC, PAUSE). 015,016 Meter usec. 5 SO Serial data output port. Unused here. 6 SI Serial data input port. Unused here, and therefore, PULL DOWN (lOkn) only is made to GND. 7 sc/f Unused. 8 TC Unused. 9 PO FL counter grid control board. POG1, PIG2, P2G3, P3G4 make correspondence

11、to each other, and lit at H and out at L . The grid is dynamically driven. The duty is about 1/4 and the frequency is about lOOHz. 10 PI FL counter grid control board. POG1, PIG2, P2G3, P3G4 make correspondence to each other, and lit at H and out at L . The grid is dynamically driven. The duty is ab

12、out 1/4 and the frequency is about lOOHz. 11 P2 FL counter grid control board. POG1, PIG2, P2G3, P3G4 make correspondence to each other, and lit at H and out at L . The grid is dynamically driven. The duty is about 1/4 and the frequency is about lOOHz. 12 P3 FL counter grid control board. POG1, PIG2

13、, P2G3, P3G4 make correspondence to each other, and lit at H and out at L . The grid is dynamically driven. The duty is about 1/4 and the frequency is about lOOHz. 13 00 FL counter a segment data output. Lit at Hand out at L . 14 01 FL counter b segment data output. Lit at H and out at L . 15 02 FL

14、counter c segment data output. Lit at H and out at L . 16 03 FL counter d segment data output. Lit at H and out at L . 17 04 FL counter e segment data output. Lit at H and out at L , 18 05 FL counter f segment data output. Lit at H and out at L . 19 06 FL counter g segment data output. Lit at H and

15、out at L . 20 07 FL counter colon segment data output. Lit at H , and out at L . 21 Vss Connected to GND. 22 RO Key input DIRECTION 23 R1 Key input DIRECTION IZ 24 R2 DPSS indication clear input L input : DPSS indication is returned to usual counter indication by hardware regardless of the current m

16、echanical motions. H input; DPSS is kept until series of motions terminate during DPSS indication. 25 R3 Key input COUNTER RESET 26 R4 Key input BS 27 R5 Key input IS 28 R6 Key input PAUSE 29 R7 Key input REW 30 R8 Key input FF 31 R9 Key input REVERSE PLAY 32 R10 Key input FORWARD PLAY 33 Ril Key in

17、put STOP 34 R12 Index scan signal input port. Index scan at H , and index scan is cancelled at L . 35 R13 Head direction detect board. FORWARD at H , and REVERSE at L . 36 R14 Unused. 37 R15 FORWARD PLAY LED drive. Voltage (5V) is supplied to F.PLAY LED anode at L . 38 KO DPSS signal input port. H w

18、ith music and L between musics. 39 KI Motor running status detect port. L during FF, REW, CUE, REWIND; H in other status. 40 K2 Motor running status detect port. H while the tape is running in FORWARD direction, andzyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA L in other statuses. 41 K3 Motor

19、 running status detect port. H while the tape is running in REVEERSE direction, and L in other statuses. 42 Vcc Power supply terminal 4.55.5V. 6 KK-747R CIRCUIT DESCRIPTION Description of FL counter indication (DPSS ihdication) Item Description Feed SEARCH (FF SEARCH) Number of jumped musics; The nu

20、mber of times FF (REW) ley was pressed is indicated. However, in the case where unrecorded portion is continued for 540msec or jonger in CUE status after FF (REW) jcey was pressed for the first time and second pressing of FF (REW) ley was not made in the mean time, the number of times of jumping, i.

21、e., the indication is 0 1 . 16 is indicated at maximum. Rewind SEARCH (REW SEARCH) Number of jumped musics; The number of times REW (FF) jey was pressed is indicated. 16 is indicated at maximum. One music repeat The number of times of repeating at the present time is indicated. 16 is indicated at ma

22、ximum, and reset to usuaj counter occurs at the 17th time. Dush NORMAL, DOLBY: OFF, I NPUT; LI NE O ci Bs = 0. 775V I REC/ PLAY HEAD 1 DEMAGNETI ZATI O - POI ER: OPF Re nov e t he c a s s e t t e door . REC/ PLAY head De a a gne t i z e t he BEC/ PLAY head wi t h a head demagnet i z er . 2 CLEANI NG

23、 -, -PLAY REC/ PLAY head er ase head, c a ps t a n, Pi nc h r ol l er . Cl ean t he REC/ PLAY head er as e head, c aps t an and Pi nc h r ol l er usi ng a c ot t on s* ab s l i ght l y damped wi t h al c ohol . 3 AZI MUTH MTT- 114 ( B) PLAY Az i mut h adj us t - ment scr ew Adj ust t he az i mut h a

24、dj us t ment scr ew so t hat t he out put v ol t age i s max i mi z ed i n bot h f or war d and r ev er s e di r ec t i on. ( a) DC MOTOR ( i ) TAPE SPEED MTT- l l l D ( B) PLAY Tr i B i i ng pot en- t i omet er i n t he DC mot or Adj ust t he t ape s peed so t hat a 3kHz si gnal i s pr oduc ed at t

25、 he cent er of t he t ape. n PC BOARD PLAYBACK LEVEL MTT- 150 ( B) PLAY VR3 ( L) VR4 ( R) Out put l ev el ; - 3. 8dBs ( SOOmV) PLAYBACK LEVEL MTT- Z56 ( B) PLAY VR3 ( L) VR4 ( R) Out put l ev el ; - 6. 5dBs( 370i nV) PLAYBACK LEVEL MTT- 256U ( B) PLAY VR3 ( L) VR4 ( R) Out put l ev el ; - 2. 5dBs( 6

26、00i i i ) BI AS CRRENT ( A) I k Hz , - 30dBs l Ok Hz , - 30dBs ( B) Adj us t REC and BALANCE so t hat t he REC moni t or out put becoBi es - 26dBs at I k Hz , t hen r ec or d and r epr oduc e s i gnal of I kHz and l OkHz i n al t er nat i on. VR9 ( L) VRI O ( R) Rec or d I kHz and l OkHz i n al t er

27、 nat i on and adj ust t he v ar i abl e r es i s t or s whi ch c ont r ol t he bi as cur r ent so t hat t he s ame pl ay bac k l evel i s obt ai ned. RECORD LEVEL ( A) I k Hz , - 30dBs ( B) Rec or d and r epr oduc e a I kHz s i gnal under t he c ondi t i ons set i n . VE5 ( L) YE6 ( R) Adj ust t he

28、v ar i abl e r es i s t or s so t hat a pl ay bac k l evel of - 26dBs i s obt ai ned. LED PEAK LEVEL METER ( A) I k Hz , - 40dBs ( B) REC PAUSE Adj ust REC and BALANCE so t hat t he Bi oni t or out put i s - 36dBs at I k Hz . VRl l ( L) VR12 ( R) - 30dB LED segment i s c ompl et el y l i t . 8 KK-74

29、7R REGLAGE REGLAGE DE REGLAGE DE REGLAGE DU MAGNETO POINTS DE r ITEM L ENTREE LA SORTIE -PflONE A CASSETTE L ALIGNEMENT ALIGNER POUR FIG. SECTION DU MAGNETOPHONE TAPE: NORMAL, DOLBY: OFF, ENTREE: LINE OdBs = 0, 775V 1 TETE DENREGISTREMENT/LECTURE Demagntiser l a tte 1 DEMAGNETISATION POKER: OFF Eloi

30、gner l a porte. Tte DENREGISTREMENT/ LECTURE DENREGISTREMENT/LECTURE avec un dmagntiseur de tte. Tte Nettoyer l a tte DENREGISTREMENT/ D ENREGISTREMENT/LECTURE 2 NETTOYAGE PLAY LECTURE tte deffacement. cabestan, galetpresseur. l a tte deffacement. i e cabestan et Ie galetpresseur avec un coton-tige

31、lgrement imbib dalcool. Ajuster l a v i s de rglage de 1 azimut de fa?on que l a 3 AZIMUT MTT-114 (B) PLAY Vis d azimut tension de s o r t i e s o i t maximale a I a fois en avant et en arrire. de l a bande dessai. (a) MOTEUR CC Rgler l a v i t e s s e de bande ( i ) VITESSE DE DEFILEMENT MTT-lUD (B

32、) PLAY Rsistance ajustable du moteur CC de fason qu un signal de 3kHz soit produit au centre de l a bande. n PLAQUE IMPRIMEE MTT-150 Niveau de s o r t i e : -3,8dBs(500mV) NIVEAU DE MTT-256 (B) PLAY VR3 (G) Niveau de s o r t i e : -6,5dBs(370mV) LECTURE MTT-256U VR4 (D) Niveau de s o r t i e : - 2,5

33、dBs(600mV) Rgler REC et BALANCE de facon que l a s o r t i e de Enregistrer un signal de (A) moniteur REC s o i t IkHz et lOkHz en alternance COURANT DE IkHz. -30dBs (B) de -26dBs IkHz, VR9 (G) et ajuster les rsistances POLARISATION lOkHz. -30dBs puis enregistrer et reproduire des signaux de IkHz et

34、 lOkHz en alternance. VRIO (D) v a r i a b l e s qui commandent Ie courant de polarit de faton a obtenir Ie mme niveau de lecture. E n r e g i s t r e r et reproduire un Ajuster l e s rsistances NIVEAU (A) (B) signal de IkHz VR5 (G) v a r i a b l e s de fa?on a D ENREGISTREMENT IkHz. -SOdBs dans l e

35、 s conditions prcises en . VR6 (D) obtenir un niveau de lecture de -26dBs. REC PAUSE INDICATEUR DE Ajuster REC et Le segment de diode NIVEAU DE CRETE (A) (B) BALANCE de facon 4 VRll (G) LED -30dB s o i t compltement A DIODE LED IkHz. -40dBs ce que l a s o t i e moniteur s o i t de -36dBs i IkHz. VR1

36、2 (D) allum. 9 K K -747R ABG LEI CH EI NGANGS-AUSGANGS-KASSETTENGERST-ABGLEI CH NR. GEGENSTAND EI NSTELLUNG EI NSTELLUNG EI NSTELLUNG PUNKTE ABGLEI CHEN FuR ABB. CASSETTEN- DECK- ABTEI LUNG TAPE; NORMAL, DOLBY: OFF, EI NGANG: LI NE 0dBs = 0, 775V I AUFNAHME/ I I EDERGABE- KOPF POKER: OFF Ent magnet

37、i s l er ung von dem 1 ESTMAGNETI - SI ERUNG Den Kas s et t enf ac h dec k el oben her aus z i ehen. AFNAHME/ KI EDERGABE- Kopf AUFNAHME/ UI EDERGABE- Kopf ml t ei nem Tonk opf Ent magnet i s i er ungs dr os s el . AFNAHME/ AUFNAH) i l E/ ! EDERGABE- Kopf . I EDERGABE- Kopf Losct i kopf . Tonwel l e

38、zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA und 2 8EI NI GUNG PLAY Ls c hk opf , Tonwel l e, Andr uc k r ol I e. Andr uc k r ol l e mi t ei nem l ei cl i t mi t Al kohol bef eucl i t et en W at t ebaus c h r ei ni gen. Di e Az i mut - J us t i er s c hr aube so ei ns t el l en. das di e 3 A

39、ZI MUT- EI NSTELLUNG MT T - I U ( B) PLAY Az i mut - Ei ns t el I s c hr aube max i mal e Aus gangs s pannung i n Vor s r t s - Rev er s er i c ht ung und er z i el t . ( a) GLEI CHSTROMMOTOR Di e Bandges c hi ndi gk ei t ( i ) BANDGESCH- fI NDI GKEI T MT T - UI D ( B) PLAY Tr i m i i i er pot en- t

40、 i omet er am Gl ei c hs t r ommot or so j us t i er en.zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA da B ei n 3kHz Si gnal auf der Mi t t e des Bands er z eugt wi r d. n GEDRUCKTE SCHALTPLATTE l l TT- 150 Aus gangs pegel : - 3, 8dBs ( 500mV) I I EDERGABE-MTT- 256 ( B) PLAY VR3 ( L) Aus gang

41、s pegel : - 6. 5dBs( 370i i i V) PEGEL MTT- 256U VR4 ( R) Aus gangs pegel : - 2, 5dBs ( 600mY) REC und BALANCE so j us t i er en, daB der REC Moni t or aus gang Si gnal e von I kHz und l OkHz ( A) - 26dBs bei I kHz abwec hs el nd auf nehmen und LEERLAUFSTROM I k Hz . - 30dBs l Ok Hz . - 30dBs ( B) w

42、l r d, und danac h abwec hs el nd Si gnal e von I kHz und l OkHz auf nehmen und * i eder geben. VR9 ( L) VRI O ( R) di e Regel wi der s t ande, di e den Vor magnet i s i er ugs s t r om r egel n, so j us t i er en, das der gl ei c he Ki eder gabepegel er z i el t wi r d. Ei n I kHz Si gnal unt er de

43、n i n Punkt Di e Regel wi der s t s nde so AUFNAHMEPEGEL ( A) I k Hz , - 30dBs ( B) bes c hr i ebenen Bedi ngungen auf nehmen und r epr oduz i er en. R5 ( L) VR6 ( R) j us t i er en, das ei n wi eder gabepegel von - 26dBs er z i el t wi r d. REC PAUSE REC und BALANCE so Di e Regel wi der s t s nde s

44、o LED SPI TZEN-( A) ( B) ei ns t el l en,daB VRl l ( L) j us t i er en. daB das - 30dB PEGELMESSER I k Hz . - 40dBs der Koni t or aus gang bei I k Hz . - 36dBs i s t . VR12 ( R) Segment v ol l s t i ndi g l euc ht et . 10 KX-747R ADJUSTM ENT/REGLAGE/ABGLEI CH 1. TEST TA PE 1 -1 . Recordi ng system a

45、dj ust tape Nor. :A C -2 2 3 (T D K ) Cr02 :A C -5 1 2 (T D K ) M ET A L :A C -7 1 2 (T D K ) 1 2. Pl ayback system adj ust tape W ow fl utter and tape speed Pl ayback l evel Pl ayback l evel and f characteri sti c Pl ayback l evel and f characteri sti c A zi m uth M TT-111 D M TT-150 M TT-256 M TT-

46、256U M TT-114 2. M EA N I N G SO FT ERM S 2 1. Speci f i ed recordi ng l evel The recordi ng l evel requi red for obtai ni ng an output l evel that i s equal to the 315Hz pl ayback output of a Standard tape of ful l m agneti c fl ux 16m M (= 160 nW b/m ) i s m eant. 2 2. Speci f l ed recordi ng stat

47、us The Status w here the speci fi ed i nput l evel of 1kHz, -lO dB s i s i nput to LIN E I N and the LI N E di al i s adj usted so that recordi ng can be m ade at the speci - fi ed recordi ng l evel (LIN E O U T i s -6 dB s at thi s ti m e) i s m eant. 2 3. Speci fi ed i nput l evel The i nput l eve

48、l w hi ch i s the reference requi red for obtai ni ng the speci fi ed recordi ng l evel i s m eant. The l evel at the i nput term i nal i s of the fol l ow i ng val ue. LIN E I N PUT -lO dBs (O V U) 2 4. Speci fi ed output l evel The l evel obtai ned at LI N E O U T at the ti m e w hen si gnal s of 315Hz of a Standard tape of ful l m agneti