Jvc-KSFX-270-Service-Manual(1) 电路图 维修手册.pdf

《Jvc-KSFX-270-Service-Manual(1) 电路图 维修手册.pdf》由会员分享，可在线阅读，更多相关《Jvc-KSFX-270-Service-Manual(1) 电路图 维修手册.pdf（48页珍藏版）》请在收音机爱好者资料库上搜索。

1、SERVICE MANUAL CASSETTE RECEIVER No.49582 Dec. 2000 COPYRIGHT 2000 VICTOR COMPANY OF JAPAN, LTD. KS-FX270 KS-FX270 Area Suffix J - Northern America Contents Safety precaution Disassembly method Adjustment method Description of major ICs 1-2 1-3 1-12 1-16 This service manual is printed on 100% recycl

2、ed paper. Scan Music Multi MO DISPDISP SCANSCAN LOUDLOUD 89101 1127 VCR 32 RadioFans.CN 收音机爱 好者资料库 KS-FX270 1-2 ! Burrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system. Safety precaution Radio

3、Fans.CN 收音机爱 好者资料库 KS-FX270 1-3 Press the eject button in the lower right part of the front panel. Remove the front panel assembly from the body. 1. Removing the front panel assembly (See Fig.1) Prior to performing the following procedure, remove the front panel assembly. Release the four joint tabs

4、 a on both sides of the front chassis assembly and remove the front chassis assembly toward the front. 1. Removing the front chassis assembly (See Fig.2 and 3) Disassembly method Fig.1 Fig.2 Fig.3 Front panel assembly Eject button Tab a Tab a Front chassis assembly Front chassis assembly Heat sink T

5、ab a Tab a RadioFans.CN 收音机爱 好者资料库 KS-FX270 1-4 Remove the three screws A on the left side of the body. 1. Removing the heat sink (See Fig.4) Prior to performing the following procedure, remove the front panel assembly, the front chassis assembly and the heat sink. Turn over the body and unjoint the

6、 five joints b with the bottom cover and the body using a screwdriver. 1. Removing the bottom cover (See Fig.5 and 6) Fig.4 Fig.5 Fig.6 Heat sink A A Joints b Joints b Joint b Joints b Joints b Joint b Bottom cover Bottom cover Rear panel Rear panel KS-FX270 1-5 Prior to performing the following pro

7、cedure, remove the front panel assembly, the front chassis assembly, the heat sink and the bottom cover. Remove the screw B, the four screws C and the two screws D attaching the rear bracket on the back of the body. Remove the rear panel. Remove the two screws E attaching the main board on the botto

8、m of the body. Disconnect connector CN701 on the main board in the direction of the arrow. 1. 2. Removing the main board (See Fig.7 and 8) Prior to performing the following procedure, remove the front panel assembly, the front chassis assembly, the heat sink, the bottom cover and the main board. Rem

9、ove the four screws F attaching the cassette mechanism section on the back of the top chassis. 1. Removing the cassette mechanism section (See Fig.9) Fig.7 Fig.8 Fig.9 Rear panel B D D C C Main board E E CN901 Cassette mechanism section F F FF Top chassis C KS-FX270 1-6 Prior to performing the follo

10、wing procedure, remove the front panel assembly. Remove the four screws G attaching the rear cover on the back of the front panel assembly. Unjoint the six joints c with the front panel and the rear cover. Remove the control switch board on the back of the front panel. 1. 2. 3. Removing the control

11、switch board (See Fig.10 to 12) Fig.10 Fig.11 Fig.12 G G G G Rear cover Joints c Joints c Front panel Rear cover Front panel Control switch board KS-FX270 1-7 For the 6pin harness extending from connector CN402 on the head amplifier P.W.B, disconnect it from the head relay P.W.B. Disconnect the card

12、 wire from connector CN403 on the head amplifier P.W.B. Remove the screw A attaching the head amplifier P.W.B. Move the tab a as shown in Fig.2 and remove the head amplifier P.W.B. while moving it in the direction of the arrow. 1. 2. 3. 4. Removing the head amplifier P.W.B. (See Fig.1 and 2) Disconn

13、ect the 6pin harness from connector CN402 and the card wire from CN403 on the head amplifier P.W.B. (Refer to Fig.1 and 2). Remove the four screws B on the bottom of the cassette mechanism. 1. 2. Removing the cassette mechanism assembly (See Fig.1 to 3) Fig.1 Cassette mechanism assy Head relay P.W.B

14、. 6pin harness CN402 CN403 CN402 Head amplifier P.W.B. Fig.2 Tab a Head amplifier P.W.B. Fig.3 Cassette mechanism assy B B A Head amplifier P.W.B. CN403 KS-FX270 1-8 Unsolder the soldering b on the head relay P.W.B. Remove the screw C attaching the head relay P.W.B. Remove the head relay P.W.B. in t

15、he direction of the arrow while releasing the two joints c. 1. 2. 3. Removing the head relay P.W.B. (See Fig.4) Remove the E washer attaching the load arm using a pincette or something like that and remove the spring d. Move the part of the load arm marked upwards to release it from the axis of rota

16、tion. Then rotate the load arm in the direction of the arrow to remove it from the cach. 1. 2. Removing the load arm (See Fig.5) Prior to performing the following procedure, remove the head relay P.W.B. Remove the screw D attaching the sub chassis. Push the tab e in the direction of the arrow to det

17、ach the one side of the sub chassis. Then release the sub chassis from the tab f. 1. 2. Removing the sub chassis (See Fig.6) Prior to performing the following procedure, remove the head relay P.W.B., the load arm and the sub chassis. Remove the screw E attaching the reinforce bracket. Remove the rei

18、nforce bracket. Push the tab g fixing the cassette holder in the direction of the arrow and open the cassette holder and the holder arm upward until they stop at an angle of 45 degrees. Move the two joints h to the side and remove the cassette holder and the holder arm from the shaft. 1. 2. 3. Remov

19、ing the cassette holder and the holder arm in the eject mode (See Fig.7 and 8) Fig.4C Soldering b Joint c Fig.6 Tab f D Tab e Cach Head relay P.W.B. Head relay P.W.B. Fig.7 Reinforce bracket Reinforce bracket E Cassette holder Sub chassis Head relay P.W.B. Joint h Holder arm Load arm Joint h tab g F

20、ig.5 Spring d Load arm E washer Cassette mecha chassis KS-FX270 1-9 Prior to performing the following procedure, remove the head relay P.W.B.and the sub chassis. Remove the two screws F attaching the play head (The spring under the play head comes off at the same time). 1. Removing the play head (Se

21、e Fig.9) Prior to performing the following procedure, remove the head relay P.W.B.and the sub chassis. Push each tab i in the direction of the arrow and pull out the pinch rollers on both sides. 1. Removing the pinch roller assy (See Fig.9) Unsolder the soldering j on the reel disc P.W.B. Push the s

22、even tabs k on the bottom of the cassette mechanism assembly in the direction of the arrow. 1. 2. Removing the reel disc P.W.B. (See Fig.10) Unsolder the two soldering l of the motor and the sub motor. Release the sub motor from the three tabs m. Push the sub motor upward and pull out it. Remove the

23、 belt on the bottom of the cassette mechanism assembly and remove the two screws G attaching the motor. 1. 2. 3. Removing the motor and the sub motor (See Fig.10 and 11) The motors can be detached before removing the load arm. ATTENTION: Fig.8 Cassette holder and holder arm Joint h Shaft Shaft Joint

24、 h Fig.9 Tab i Pinch roller assyPinch roller assy F Play head Spring Fig.11 Sub motor Tab m Load arm Motor Soldering l Tab m Soldering l Tab m Soldering j Pinch roller assy Tab i Tab i Tab i Fig.10 Cassette mechanism assy Tabs k Reel disc P.W.B. Soldering j Tabs k G G Motor Belt Flyhwheel KS-FX270 1

25、-10 Prior to performing the following procedure, remove the head relay P.W.B, the load arm, the sub chassis, the cassette holder, the holder arm and the reel disc P.W.B. Remove the belt on the bottom of the cassette mechanism assy. Remove the slit washer attaching the flywheel on the upper side of t

26、he cassette mechanism assy and pull out the flywheel downward. Then remove another flywheel in the same way. 1. 2. 3. Removing the flywheel (See Fig.10 and 12) Prior to performing the following procedure, remove the head relay P.W.B, the load arm, the sub chassis, the cassette holder and the holder

27、arm. Disengage the part n inside of the reel driver which engages with the shaft, using a pincette or something like that. Then remove the reel driver from the shaft. Remove the reel driver spring and the reel table. 1. 2. Removing the reel disc assy( ) (See Fig.12 to 14) When reassembling, make sur

28、e to use a new slit washer. ATTENTION: Fig.10 Cassette mechanism assy Tab k Reel disc P.W.B. Soldering j Tab k G G Motor Belt Flyhwheel Fig.12 Plate The part n Reel driver Reel disc assy( ) Push aside the gear Tabs o Reel disc assy( ) The part n Reel driver Tab o Fig.13 Reel driver Shaft The part n

29、Fig.14 Reel driver spring Reel table Slit washer Slit washer KS-FX270 1-11 Release the plate from the three tabs o. Push aside the gear over the reel table using a pincette or something like that. Remove the reel disc assy ( ) as with the reel disc assy ( ). 1. 2. 3. Removing the reel disc assy( ) (

30、See Fig.12 to 15) Do not break the front panel tab fitted to the metal cover. ATTENTION: Prior to performing the following procedure, remove the reel disc ( ). ATTENTION: Fig.15 Push aside the gear and reattach the reel disc Assy( ). Reel disc assy( ) KS-FX270 1-12 Adjustment method Test instruments

31、 reqired for adjustment 1. Digital osclloscope(100MHz) 2. Frequency Counter meter 3. Electric voltmeter 4. Wow & flutter meter 5. Test Tapes VT724. . for DOLBY level measurement VT739.For playback frequency measurement VT712.For wow flutter & tape speed measurement VT703. For head azimuth measuremen

32、t 6. Torque gauge. Cassette type for CTG-N (mechanism adjustment) Measuring conditions(Amplifier section) Power supply voltage. DC14.4V (10.5 - 16V) Load impedance . 4 (2Speakers connection) Line out. 20k Standard volume position Balance and Bass,Treble volume .Fader :Center(Indication0) Loudness,Do

33、lby NR,Sound,Cruise:Off Volume position is about 2V at speaker output with following conditions.Playback the test tape VT721. AM mode1000kHz/62dB,INT/400Hz,30% modulation signal on recieving. FM mono mode97.5MHz/66dB,INT/400Hz,22.5kHz deviation pilot off mono FM stereo mode 1kHz,67.5kHz dev. pilot7.

34、5kHz dev. Output level0dB(1 V,50 /open terminal) MC-109Cfor TAPA CURL confirmation (without Padd type) KS-FX270 1-13 Head section view Cassette mechanism (Surface) Arrangement of adjusting & test points Motor assembly Tape speed adjust Playback head Azimuth screw B (Reverse) Azimuth screw B (Reverse

35、) Azimuth screw A (Forward) Azimuth screw A (Forward) Playback Head KS-FX270 1-14 EXTKSRT002-18P Information for using a car audio service jig 1.Were advancing efforts to make our extension cords common for all car audio products. Please use this type of extension cord as follows. 2.As a U-shape typ

36、e top cover is employed, this type of extension cord is needed to check operation of the mechanism assembly after disassembly. 3.Extension cord : EXTKSRT002-18P ( 18 pin extension cord ) For connection between mechanism assembly and main board assembly. Check for mechanism driving section such as mo

37、tor ,etc. Disassembly method 1.Remove the bottom cover. 2.Remove the front panel assembly. 3.Remove the top cover . 4.Install the front panel. 5.Confirm that current is being carried by connecting an extension cord jig. Note Available to connect to the CP701 connector when in- stalling the front pan

38、el. Cassette mechanism Front panel assembly Main boardMain board Extension cord EXTKSRT002-18P to Main board to Cassette mechanism KS-FX270 1-15 Mechanism adjustment section ItemAdjusting & Confirmation MethodsAdjustStd. Value 1.Check to see if the reading of the frequency counter & W ow flutter met

39、er is within 2940-3090 Hz( FWD/REV ), and less than 0.35% ( JIS RMS ). 2.In case of out of specification, adjust the motor with a built- in volume resistor . 1.Play the test tape ( VT724 : 1kHz ) back and set the volume position at 2V . 2.Play the test tape ( VT739 )back and confirm 0 3dB at1kHz/ 10

40、kHz and -4+2dB at 1kHz/63Hz. 3.When 10kHz is out of specification, it will be necessary to read adjust the azimuth. Phase 0 45 Built-in volume resistor Tape Speed 2940-3090Hz Wow&Flutter Less than 0.35% (JIS RMS) Speaker out 1kHz/10kHz : 0dB 3dB, 63Hz/1kHz : -4dB+2dB, 1. Tape running adjustment 2. A

41、zimuth adjustment confirmation a) At forward play mode, make adjustment of peak of Lch / Rch output with Azimuth screw A. * For Oscilloscope litharge corrugation, set 45 as standard. b) At Reverse play mode, make adjustment of peak of Lch / Rch output with Azimuth screw B. * For Oscilloscope litharg

42、e corrugation, set 45 as standard. c) With AC volt meter confirm the difference of output for 4ch between Lch / Rch at forward play mode and Lch / Rch Reverse play mode being within 3.0dB. d) After operation, make confirmation of Lch / Rch azimuth output being within 1.0dB from adjustment value. a)

43、At Forward playmode, using mirror tape, make adjustment with Azimuth screw A and Azimuth screw B, without curl of 4 parts of head tape guide. b) At Reverse play mode, using mirror tape, make adjustment with Azimuth screw A and Azimuth screw B, without tape curl of 4 parts of head guide. c) At Forwar

44、d / Reverse play mode, make confirmation of no tape curl of 4 parts of head tape guide. 2.Tape Speed and Wow & Flutter 3.Playback Frequency response Azimuth screw A Azimuth screw B HEAD Tape guide OK HEADTAPE Tape curl NG KS-FX270 1-16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 32 31 30 29 28 27 26 25 2

45、4 23 22 21 20 19 18 17 SDA GND OUTLR OUTLF TL B2L B1L IVL ILL QSL IDL MUTE ICL IMD IBL IAL SCL VCC OUTRR OUTRF TR B2R B1R IVR ILR QSR IDR Vref ICR CAP IBR IAR CD-CH TAPE TUNER POWER SUPPLY SOURCE SELECTOR VOLUME 1 +20 to -31 dB LOUDNESS LEFT BASS LEFT +15 dB TREBLE LEFT +12 dB BASS RIGHT +15 dB TREB

46、LE RIGHT +12 dB MUTE FUNCTION ZERO CROSS DETECTOR VOLUME 2 0 to 55 dB BALANCE FENDER REAR VOLUME 2 0 to 55 dB BALANCE FENDER FRONT HC BUS REC VOLUME 2 0 to -55dB BALANCE FENDER FRONT VOLUME 2 0 to -55dB BALANCE FENDER REAR VOLUME 1 +20 to -31 dB LOUDNESS RIGHT LOGIC 21 31 2 19 16 15 13 11 22 20 18 1

47、7 14 23252426 2728 30 29 1 32 3 4 108976512 1.Pin layout 3.Pin functions 2.Block diagram 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Pin No. Pin No. 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 SDA GND OUTLR OUTLF TL B2L B1L IVL ILL QSL IDL MUTE ICL IMO IBL IAL Serial data input/output. Ground. output

48、 left rear. output left front. Treble control capacitor left channel or input from an external equalizer. Bass control capacitor left channel or output to an external equalizer. Bass control capacitor left channel. Input volume 1. left control part. Input loudness. left control part. Output source s

49、elector. left channel. Not used Not used Input C left source. Not used Input B left source. Input A left source. I/O - O O I - - I I O - - I - I I Symbol I/O Symbol I/O Input A right source. Input B right source. Electronic filtering for supply. Input C right source. Reference voltage (0.5Vcc) Not used Output source selector ri