Panasonic JU-475-4 Manual
Contents
1. 3 Reverse the above procedure to reinstall 4 After reinstallation the adjustments necessary upon reinstallation of the cartridge guide as described in section 12 7 Fig 12 10 Drive Motor Removal 12 11 LED Assembly Removal and Installation 1 Remove the clamp handle and front plate as described in section 12 2 2 Disconnect the J8 connector from PCB 3 Remove the LED assembly by sliding it slant from the cartridge guide assembiv 4 Reverse the above procedure to reinstall 5 The LED can be removed and installed as it is Putin groove of rear section Notch section O Holder LED LED Front Fig 12 11 LED Assembly Removal 21 12 12 Lifter Unit Removal and Installation 1 Remove the clamp assembly as described in section 12 5 2 Remove the lifter shaft clamping retaining ring and draw out the lifter shaft 3 Remove the lifter unit 4 Reverse the above procedure to reinstall Retaining Ring EN Lifter Shaft Clamp Assembly Fig 12 12 Lifter Unit Removal 12 13 Media Lifter Removal and Installation 1 Remove the clamp assembly as described in section 12 5 2 Remove the lifter shaft clamping retaining ring draw out the lifter shaft 3 Remove the media lifter 4 Reverse the above procedure to reinstall Media Lifter Spring Cartridge Guide Lifter Shaft Retaining Ring Fig 12 13 Media Lifter Removal 22 122. Service Manual Flexible Disk Storage Drive JU 475 4 Panasonic so 10 11 12 13 14 15 16 17 18 CONTENTS PARTI Page INTRODUCTION z a A A A eee a a 1 MODELS AND MODEL NUMBERS neneneneenaeetensusesusneee nen iGO 1 2 1 5 25inch FOD SONOS ze a b b o td Hud 1 SPECIAL TOOLS u isba can eos dE ij Wi E GTE SIS m ele W a A 1 OUTLINE OF MAINTENANCE 2 44 AligamentDiskette issir Idi mia Ta e bt okt 2 42 Exerciser gt pcs tute se a L A a ti us 2 DIAGNOSTIC PROCEDURES 2 5 Error Symptom Recognition LL rr asa aN S 2 5 2 Soft Error Detection and Correction 2 5 3 Write ETO sortere di ia ame ae PRESSE ADE e EPO Da AD ia eat 2 5 4 Read Error ido A 3 5 5 A iD ia kt a ae tema ahh daa eddies Veke DEA 3 5 6 Interchangeability Error 22 26 ce cece r rr ran rnnnzrenzza 3 TROUBLE ANALYSIS assi sais Se pindadele ari dada ww vine bee Melb edie tee tee Waves a ede we weet eee E 3 6 1 Trouble Analysis Procedure 2 2 ll corro 3 6 2 Troubleshooting Flow Chart 2 22 rr eee e nn 4 6 3 Trouble Analysis Table 0 ererereeeneenenneseeeeeraseeeera seene 5 PREVENTIVE MAINTENANCE 6 SPECIFICATION
3. JU 475 4AGG Component Side Top FOL0128084 16 tips yr FRA 6283 i icz z XTAL 20 mut 2 Me 3 H sir RPI 12 R61 04 D3 4 sil C34 PMP C24 R21 R26 R25 000 e mma ali 12 11 28 CIRCUIT BOARD JU 475 4AGG Solder Side Bottom ll1I11111111 BEEN 5 ERA FPK04162B3 A NTP S70 T 29 0 MEDIA TRACK 00 WRITE STEPPER ACTIVITY HEAD DETECTOR DETECTOR PROTECT MOTOR LED LOAD DETECTOR gt 9 ME ss Y e DD MOTOR W yt A INDEX DETECTOR 5 lt Y1 00 XJVBL OND NH tn 03345 AG NO 8010W ORIVE SELECT 4 6 INDEX ls DRIVE SELECT A 110 EO ns AST Ot 7 DRECTION SELECT 6 TRA CARA ANE STR 2 OLT EE a HEAD 1 33 odd number Side 1 SIGNAL GND SERES Nirti TO HOST POWER SUPPLY TO HOST SIGNAL Iz siv N l INVYOVIGC NDOTA SL Matsushita Communication Industrial Co Ltd Memorv Svstems Division
4. R i a 8 o T 7 fo oO D 3 a ra o 25 REPLACEMENT PARTS LIST FOR PCB 2 MODEL JU 475 4AGG CTO momania ss gt QI OO XN42121X Transistor TT 1 2 Q2 3SKI144 1X Transistr 1 2 P j Q5 8 UN2211 TX Transistor f 2 2 Q fun2111 TX Transistor 2 T RI9 FRA001008151 ChipResistor 9 j RIO OO ERJ6GEYJ392V ChipResstr 114 1 1 J RIT JERIGGEYG392V Chip Resistor 1 1 1 R12 TJERJ6GEYGS12V ChipResistor 4 RI3 fERJ6GEYJ392V chipResistor 1 T Ri5 JERJGGEVJ392V ChipResistor 1 Ri JERJ6GEYJ104V ChipResistor 11 1 b Chip Resistor 3 j Chip Resistor BREE kiki EN R22 fERJ6GEYJ821V _ ChipResitr 1 1 J R23 JERIGGEYJ392V ChipResistor 1 lo 1 R24 fERJ6GEYJ331V Chipresistor 1 1 1 j R25 26 FRA00100B151 ChipResistor 12 R28 JERJGGEYG3G3V ChipResistor 114 Chip Resistor GEE a R30 ERJ6GEYG363V ChipResistor R31 JERI6GEYG203V Chipresistor 1 1 R32 JERJ6GEYG363V ChipResistor 1 R33 JERIGGEYG203V _ ChipResistor 1 I R34 ERJ6GEYG363V ChipResistor I Chip Resistor 1 A R36 OO ERJGGEYJ392v ChipResistor 4 1 R37 39 ERJ6GEYJ102V ChipResistor 13 J RO ERJ6GEYJ163V _ ChipResitr 11 1 ll R41 42 TERIGGEYJ362V ChipResistor 17 1 J R43 ERG1SJ271V___ Metal Film Oxide Resis
5. Write 1F or 2F All O sor 1 s 4 Head load 5 25inch FDD with optional head loader 5 Recalibration to track 0 The exerciser has switches and indicators to execute a specified function DIAGNOSTIC PROCEDURES Error Symptom Recognition Errors that occur because of the wrong operating procedure wrong programming the use of a defective diskette or soft errors due to external causes such as contaminated air and random electrical noise are often attributed to an FDD failure Unless a visual inspection of the FDD reveals an evident assembly fault or a defect always confirm errors with another good diskette and another known good FDD Soft Error Detection and Correction Soft errors are normally caused by the following 1 Contamination between read write heads and diskette This kind of contamination can be easily eliminated by the liner in the diskette Please follow the appropriate procedures provided with the cleaning diskette 2 Random electrical noise normally a few microseconds or less 3 Small defects in written data and or track not detected during write operation may cause soft errors during read 4 Faulty grounding of the FDD or host system can also cause soft errors 5 Wrong motor speed is another cause of soft errors Take the following steps on the controller side to recover from the soft errors mentioned above 1 Read the track again ten times or until the data is recovered 2 if step 1 above f
6. YTF3C07194B3 Media Lifter Clamp Cam Assembly 8 9 0 z gt um W m edia Lift Spring ollet Assembly rite Protect Sensor etaining Ring etaining Ring ock Cam 34 333D46624770 LockSpring adA 36 YTF2E12870B1 Cartridge Guide lamp Bearing B lamp Bearing A ad B 40 YTUF45IDX8 Index Sensor Media Sensor Dummy Diskette RSP Recommend Service Parts per 1 000 Units Caution 1 PCB assembly with mark NLA is no longer available after production discontinuation of the complete set 2 When you order the aforementioned parts be sure to specify Part No of the parts ordered Q N JI 24 15 REPLACEMENT PARTS LIST FOR PCB 1 MODEL JU 475 4AGG ECEA1EKS330E Electrolyte Capacitor SR585F105Z 1 Chip Capacitor Chip Capacitor 12 Chip Capacitor Chip Capacitor 1 MCH215A101JK_ ChipCapacitor j 1 C15 16 MCH212F1042K_ ChipCapacitor 1 C i S 2 2 ES Q 09 No enn O O NO i O C20 21 FCC00330B 103 C25 26 MCH212F104ZK ECEA 1EKS330E Electrolvte Capacitor di ECEA 1EKS330E Electrolvte Capacitor 1 ajap N jw OM TATA TATA TN W JW 64 JIN IN N PIN OS O oo isi m O O E TI N N N N DAT o A N N A A O zm 2 e ao Q o w ke O o O 8 MCH212F104ZK MA151WK TX Diode TE E i i aa 2 3 z T n ku N N UI
7. 14 Media Sensor Assembly Removal and 1 Installation Remove the PCB as described in section 12 1 2 Remove the cartridge guide assembly as 3 4 5 described in section 12 7 Draw out the pins of the media sensor assembly from the following locations on the J3 connector No8 10 12 At that time draw out the pins with lifting the stopper on the connector Remove the media sensor assembly mounting screw and take out the media sensor assembly Reverse the above procedure to reinstall Media Sensor Lead Pin Lead Hole Fig 12 14 Media Sensor Assembly Removal 13 EXPLODED VIEW JU 475 4AGG Caution For transportation insert the dummy diskette in the drive unit and close the lever Remove the dummv diskette before use of the drive unit 23 14 REPLACEMENT PARTS LIST MODEL JU 475 4AGG Part Name amp Description Pes nse Remarks YTUF47PK4 PCB Assembly 8 YTF4H0309184 GuideRod 1 9 YTF5W0327282 FrontPanel 1 10 YTF6A01092B3 ClampHandie 7 14 XSB3 5FX Screw For Stepper Moto TT 15 X5B3 6FX Screw PCB Assembly 1 Faston 1 Front Plate 2 Drive Motor 3 Pig Tail Clamp 1 Shield Plate 2 Cartridge Guide 4 Clamp Bearing A 2 Media Sensor 1 16 YTF1E00310B4 Screw For Shield Plate crew For Track 0 Sensor Index Sensor 18 YTF3L12930B2 Base 19 YTUF5DMT 3BT Drive Motor FMD01732B4T ig Tail Clamp D Holder Assembly
8. and index sensor mounting screw respectively Reverse the above procedure to reinstall When reinstalling the write protect sensor exercise care so that the leads and write protect sensor will not project from the bottom and side of the base After index sensor installation adjust the index burst as described in section 9 8 12 7 Cartridge Guide Assembly Removal and Installation 1 Remove the PCB as described in section 12 1 2 Remove the handle and front plate as described in section 12 2 3 Remove the clamp assembly as described in section 12 5 4 Remove the write protect sensor mounting screw 5 Remove the three cartridge guide mounting screws and take out the cartridge guide assembly index Sensor Orange 6 After reinstallation adjust the collet assembly index Sensor Red asin section 12 4 step 6 and adjust the index Write Protect Sensor Black burst as in section 9 8 Write Protect Sensor Green 7 When removing or reinstalling be careful not to damage the carriage arm with the lifter index Sensor Write Protect Sensor Cartridge Guide Assembly Write Protect Sensor Fig 12 7 Cartridge Guide Assembly Removal Fig 12 6 Write Protect Sensor Assembly and Index Sensor Assembly Removal 17 12 8 Stepper Motor Assembiv Removal and 12 9 Head Carriage A
9. head load circuit Stepper motor Guide shaft contamination or damaged PCB stepper driver circuit See Item 1 See Item 4 Head disconnected Head shorted Head load bail height wrong PCB write circuit See Item 1 See Item 4 See Item 6 PCB read circuit See Item 1 See Item 4 See Item 7 Alignment Azimuth Index burst Asymmetry Limiter Track 0 Head load time Index period PCB read circuit LED part PCB IN USE circuit Write protect part Write protect circuit w VO 34pin signal failure 1 Track 0 detection failure No head loading I Read error a won t light Write protect failure 7 PREVENTIVE MAINTENANCE No preventive maintenance is necessarv for anv FDD under normal conditions However if adjustments are necessarv the procedures in this manual must be followed e Adjustments Refer to Table 8 1 1 Make a read write head radial adjustment at the specified track Sides 0 1 2 Make an index burst adjustment at the specified track Sides 0 1 3 Make an azimuth measurement at the specified track Sides 0 1 CAUTION Do not write when using alignment diskette Check that write protect sensor is properlv operating with a data diskette Note Section 9 describes the adjustment procedure in detail 8 SPECIFICATIONS Table 8 1 Specifications MINI a type Drive motor is dual speed type 300 rom e 360 rpm Parameter 1 jindexperiod Outpu
10. oscilloscope as follows SYNC VERT HORIZ 4 Write 1F 5 A read waveform is displayed on the oscilloscope as shown in Fig 9 7 6 Confirm if it satisfies the value as shown in Fig 8 1 CH 1 CH 2 Fig 9 7 Asymmetry Waveform sil 10 TEST POINTS Printed Circuit Board Top View GND Vout Vout STEP READ DATA 12 11 PANASONIC ALIGNMENT DISKETTE Table 10 1 Panasonic Alignment Diskette Index a Radial 817 128 34 TRK 34 TRK 16 TRK JA 551 JU 455 13 PART ll 12 REMOVALS AND INSTALLATIONS 12 1 PCB Removal and Installation A E Caution of the cable leading 1 Remove the four shield plate mounting screws and take out the shield plate 2 Remove the one PCB mounting screw Let the cable pass under the C guide Hook the cable to the 3 Disconnect the connectors J3 CON J4 CON J5 rib projected on the CON 17 CON J8 CON from the PCB 4 To reinstall reverse the above procedure 5 Readjustment is not necessary after PCB a 60 The cable shall not replacement protrude above A the upper face of the drive Make it flat by pressing with a finger Do not let the pig tail bitten or disconnected Do not damage or disconnect the pig tail by pressing it forcibly into the much in the PCB Fig 12 1 2 Cable Leading 12 2 FrontPlate and Handle Removal and Installation U y li li fire U 1 Op
11. S 4 assa ss a Sees GG em ama o arenaene k ie A aa a 6 ADJUSTMENTS AND VERIFICATIONS 7 9 1 Motor Speed Verification Index Period 7 9 2 Write Protect Verification Ruya uu lulus senennnnnennnzenenzznnnnnnzznrnnnnzenezznnzna 7 9 3 Head Output Verification GT Sel Ok Wack ae ean CENA oe deo nts A REESE 7 9 4 Output Modulation Verification 8 9 5 Resolution Verification ersrerreeenrresetatss nr 8 9 6 Radial Alignment Verification and Adjustment 8 9 7 Azimuth Verification curar tk lade seas para iD 9 9 8 Index Burst Verification and Adjustment _ 10 9 9 Track 0 Sensor Adjustment 10 9 10 Asymmetry Verification su S u g tau rr ih 11 TESTPOINTS sets diac oe Oy Po w san a we ees 12 PANASONIC ALIGNMENT DISKETTE 13 PARTII REMOVALS AND INSTALLATIONS 14 12 1 PCB Removal and Installation 14 12 2 Front Plate and Handle Removal and Installation 14 12 3 Track 0 Sensor Re
12. T 1 2 1 3 INTRODUCTION This service manual consists of two parts Part covers maintenance description adjustment procedures and trouble analysis and Part Il covers disassembly and reassembly procedures parts list and PCB circuits Part encompasses maintenance instructions for all Floppy Disk Drive FDD models Refer to the highlighted applicable items and perform maintenance work on the FDD Note Thisservice manuals is prepared for maintenance of the FDD Do notuse this manual for judging pass or fail criteria in inspections MODELS AND MODEL NUMBERS 5 25inch FDD Series 48TPI JA 551 le JU 455 96TPI JA 560 JA 561 JU 581 JU 585 SPECIAL TOOLS The following special tools are used for FDD maintenance Table3 1 Special Tools Tool 5 25 inch 48TPI JA 551 JU 455 JA 561 JU 465 loscilloscope Somia Probe 10 1 po Frequencycounter o Note amp Stand for the same as left 4 4 1 4 2 5 2 5 3 OUTLINE OF MAINTENANCE e The following tools are required for maintenance of an FDD Alignment Diskette Alignment diskette is used for head actuator alignment and index sensor adjustment Use the right diskette as shown in Table 8 1 Exerciser The exerciser enables you to make all adjustments and inspections necessary for an FDD Its functions include the following 1 Seek increment or alternate tracks 2 Read but no data compare 3
13. a interchangeability error which can be caused mostly by the following reasons which should be checked as follows 1 Head misalignment Refer to Adjustments and Confirmation section 9 6 2 Head output too low Refer to Confirmation section 9 3 3 Motor speed difference Refer to Adjustments and Confirmation section 9 1 4 Format incompatibility TROUBLE ANALYSIS To determine the cause of trouble whether it lies in the FDD diskette or controller replace the diskette and the FDD with good ones If the FDD is assumed faultv as a result follow the procedure below 5 Trouble Analysis Procedure FDD trouble may occur in any of the following ten forms 1 Index detection failure 2 1 O 34pin signal failure Disk Change Ready Media In Media Out 3 Track O undetectable 4 Noseek 5 Nowrite 6 Noread 7 Readerror 8 INUSE LED won t light 9 Write protect undetectable 10 No head load 5 25inch FDD with optional head loader Check with the troubleshooting flowchart in section 6 2 CAUTION Be sure to switch the power off before removing an FDD or PCB from the operating system 6 2 Troubleshooting Flow Chart Table6 1 Troubleshooting Flow Chart Problem Remains the Same after NO Diskette Replacing with Good Defective Seek NO Diskette7 Operation OK YES YES Problem z Remains the YES Cont
14. ails to recover the data access the adjacent track Then return the head to the original track 3 Repeat step 1 4 Any error that cannot be corrected by the above procedure is irrecoverable Write Error if an error occurs during write operation it is usually detected during the next revolution by performing a read operation called write check To correct an error write again and repeat a write check operation If the result is unsatisfactory after ten or more write operations perform a read operation on another track to determine whether it is the diskette or the drive that is wrong If an error persists replace the diskette and repeat the above procedure If the error still persists assume the FDD defective If the error is corrected the diskette is defective It can be thrown away 5 4 5 5 5 6 6 1 Read Error Most read errors are soft errors Data can be recovered by following the recovery procedure in section 5 2 Seek Error Seek errors are caused by the following 1 Stepper motor or stepper motor drive circuit is faulty 2 Faulty Carriage There are two ways to recover from a seek error One is to recalibrate to track 0 and seek back to the original track The other is to read the ID field check the track number on which the head is located and move the head away from it Read it again Interchangeability Error Data which is written by one FDD may not be read by another This error is called
15. cw crelooz2y cis pad a 29 A SID 1 E U 1 y 2 NC 2 D1 MA151WK O 14 0 022 c9 300 44 a 5V CB unzni sva 37 36 QB 06 1 m au gt UN2211 Ga Ra JUNZZU 9 8 o ppc rrF e o pap 8 t lk f 558 sue DRIVE SELECT 1 DSO D 1 44 PTK a a EH Z DRIVE SELECT 2 12 DS2 EM benp L RSS 7p7 A DRIVE SELECT 3 4 DSI y GE ZA DRIVE SELECT 4 8 DSaj y 8 INDEX ar LI Far D2MA122 O3MA122 F TRACK mA BE WRITE PROTECT a PSN 30 READ DATA GA wo ZYY YS 3 mr a Md H DE SELECT Z 139K EG 823 2 R1 R ZZ 2 Ri E IE gt PE 121 p IC 1 C SV 2 2 OTOR ON X B 61 NHTRO ja 3137 Wa ROW o A s RZE api gt gt MOTOR TERRIA SE I BIS BB e e Al ere STEP 20 E WS NSTEP TN 5 a GATE DATA TT sed NWROT 2 1377 WRITE GATE X2 IAEA E ST A E BER er NSTPACT ki gt 2 PCC I TT EEE NSD1 RES ee STEP MOTOR Ass R A a 4 nate y Se AAA jP 55 b H TUN NLOWHD LJ am vg ES R24 330 2 CEJ A Y NY E N USE LED SV 5V 1 Ny ir 3 L7 33JH 32 ek E ya eg 12V oowT WRITE PROTECT NM 37 SE ANIE SET ESEE MGB MA151A WRITE PROTECT PE BRE 7 L8___33UH INDEX PE Ea a c EE zy INDEX PC SY vs TP8G tsva DS MA151A TRACK 00 PC N s 5V NOTES _ TRACK DO PE i 450 CO R6i 4 7 o ZA NOT INSTALLED TRACK OG LA 378 1 4W OIL 33U125V Z RP1 gt 1kax6 MEDIA SENSOR PC 912 10 R26 MEDIA SENSOR PE TN mr 150 MEDIA SENSOR LA SJ NE 9 ne g 27 17 CIRCUIT BOARD
16. erate the lock cam of the clamp assembly and turn the clamp handle in the direction of clamping 2 Remove the clamp handle 3 Remove the two front plate mounting screws and take off the front plate 4 Reverse the above procedure to reinstall Lock Cam Fig 12 1 PCB Removal Clamp Handle Fig 12 2 Front Plate and Handle Removal 14 12 3 Track 0 Sensor Assembly Removal and 12 4 Collet Assembly Removal Installation and Installation Adjustment 1 Remove the shield plate as described in section 1 Remove the cartridge guide assembiv as 12 1 step 1 described in section 12 7 2 Disconnect the J3 connector from PCB 2 Remove the lifter unit as described in section 3 Draw out the pins the track 0 sensor assemblv 12 12 from the following locations on the J3 3 Remove the collet assembly from the guide connector No2 4 6 shaft At that time draw out the pins with lifting the 4 Reverse the above procedure to reinstall stopper on the connector 5 After reinstallation perform collet assembly 4 Remove the track 0 sensor assembiv mounting center adjustment screw and take out the track 0 sensor assembly 6 Collet assembly center adjustment 5 Reverse the above procedure to reinstall a Temporarilv fasten the cartridge guide 6 After reinstallation adjust the track 0 sensor as assembly described in section 9 9 b Inserta diskette or dummy diskette and clamp it Track 0 Blue c Clamp repeatedly a fe
17. ide 1 along line A on the pig tail clamp b Ensure that the pig tail does not come in contact with the inner wall of the base Contacting of the pig tail is allowable if the side 0 and side 1 are not overlapped each other vertically 4 Fig 12 9 2 When the carriage is on the inner most track Fig 12 9 1 Mounting of the Pig Tail Clamp a When the head carriage is on the inner most track lead the side 0 and side 1 along line B on the pig tail clamp 5 Provide a clearance of about 1mm between the side 0 and side 1 6 Ensure that there is not excessive load or protrusion at the outlet for the pig tail in the head carriage 7 Fasten the pig tail clamp with screw 8 Do not pull the pig tail by a force more than 500g after it has been clamped 9 Pull the pig tail lightly to ensure that it does not move 19 When the carriage is on an outer most track Provide a clearance of about 1 mm between the Side 0 and Side 1 approximatelv within this range Align the center with line A 777 When the carriage is on an inner most track Inner most o AJ Provide a clearance of about 1 mm between the Side 0 and Side 1 approximately within this range Fig 12 9 2 Pail Tail Leading 20 12 10 Drive Motor Removal and Installation 1 Remove the cartridge guide assembly as described in section 12 7 2 Remove the three drive motor mounting screws and take off the drive motor from the base
18. ifications in the azimuth column of Table 8 1 When B C When B gt C When B lt C Azimuth 0 Azimuth B x A Azimuth CB x A B D C A A 12 Fig 9 4 Azimuth Waveforms 9 8 Index Burst Verification and Adjustment 1 Insert an alignment diskette Seek to the track specified in the index burst column of Table 8 1 2 Set the oscilloscope in the same conditions as in section 9 7 and set horizontal deflection to 50us division 3 Check that the time from kis iela start to the first data meets the index burst specifications of Table 8 1 4 Ifthe specifications are not met adjust as follows eLoosen the index detector mounting screws enough to free the assembly e Adjust the timing to meet the specifications of Table 8 1 e Retighten the screw Check the timing again Fig 9 5 Index Timing Fig 9 S 1 Index Detector 9 9 Track 0 Sensor Adjustment IMMA 1 Setthe oscilloscope as follows TRIG SYNC VERT HORIZ 2 Step between specified tracks at in the track 0 item of Table 8 1 Turn the seek delay switch on the exerciser to adjust 3 ms seek 3 Loosen the track 0 sensor screw and Pent until the waveform on th oscilloscope appears as shown i in Fig 9 6 G Mounting screw Fig 9 6 Track O Waveform Fig 9 6 1 Track 0 Adjustment 10 9 10 Asymmetry Verification 1 Inserta work diskette 2 Step tothe track specified in the asymmetry item of Table 8 1 3 Setthe
19. moval and Installation 15 12 4 Collet Assembly Removal Installation and Adjustment 15 12 5 Clamp Assembly Removal and Installation 16 12 6 Write Protect Sensor Assembly and Index Sensor Assembly Removal and Installation 16 12 7 Cartridge Guide Assembly Removal and Installation 17 12 8 Stepper Motor Assembly Removal and Installation 18 12 9 Head Carriage Assembly Removal and Installation 18 19 12 10 Drive Motor Removal and Installation SAY 20 12 11 LED Assembly Removal and Installation 21 12 12 Lifter Unit Removal and Installation 00 Lane nee nnnn ene eee eees 21 12 13 Media Lifter Removal and Installation 22 12 14 Media Sensor Assembly Removal and Installation 22 EXPLODED VIEW L mis vedas Sue ekke malai EE sa A add 23 REPLA EMENT PARTS LIST iii iii A s i sal 24 REPLACEMENT PARTS LIST FOR PCB nnenuervenesenevasearsunneseeennne ave nn 25 26 SCHEMATIC DIAGRAM sims O died Gnd DOP owy ed 27 CIRCUIT BOARD hr a dead 28 29 BLOCK DIAGRAM ii ao 30 PAR
20. nt 2 Step to the track specified in the radial alignment column of Table 8 1 3 Leavethe oscilloscope in the same condition as mentioned in section 9 3 e CatsEye System 4 Check the output waveforms for sides 0 and 1 They should appear as in Fig 9 2 5 The two waveforms should appear in the amplitude ratio in the radial alignment column of Table 8 1 or better 6 I the specified ratio is not satisfied loosen the two mounting screws for the stepper motor 7 Move the stepper motor along the base bv hand until the two waveforms assume approximatelv the same amplitude and retighten the mounting screws See Fig 9 2 8 Step the head outward track 0 and inward track 79 and confirm that the adjustment has been completed 9 After the radial adjustment be sure to confirm track 0 sensor adjustment as described in section 9 9 Note Alignments on sides 0 and 1 are adjusted at the factory If they are misaligned adjust them to meet the specifications of Table 8 1 Mounting screws when A gt B x 100 0 Fig 9 2 Radial Alignment Waveforms CATS EYE Fig 9 2 1 Stepper Motor Mounting Screws 9 7 Azimuth Verification 1 Insert an alignment diskette Seek to the track specified in the azimuth column of Table 8 1 2 Set the oscilloscope in the same conditions as in section 9 3 and set horizontal deflection to 0 5 ms division 3 Measure as shown below 4 Confirm that the measured value meets the spec
21. roller Write SW On Same after Replacing Defective with Good FDD2 NO Write Waveform NO Run the operating svstem and er Pee check Record all diagnostic E information on tracks and sectors as far as the program permits YES Write SW Off install Exerciser on FDD Power SW YES Read Waveform DCSW On on Oscilloscope Drive Select SW OK Head load SW gt On NO Index tame NO Check item 1 OK after BO Flashes Table 6 2 head cleaning YES YES 1 0 34pin NO Check Item 2 FDD online test signal output Table6 2 OK YES Read YES Error CRC Recal SW Error On NO FDD Track 0 NO Check kem 3 IN USE LED NO Lamp Lights at Table 6 2 Lights Track 0 YES YES When Head Load option Write NO Head Load Operation OK NO Check Item 4 Table 6 2 YES YES Protect Lamp Lights END Check Item 5 Table 6 2 Check Item 6 Table 6 2 Check Item 7 Table 6 2 Check Item 8 Table 6 2 Check item 9 Table 6 2 Check Item 10 Table 6 2 6 3 Trouble Analysis Table Table 6 2 Trouble Analysis men vm s G Index detection failure 1 Colletpartfaulty Drive motor control PCB Drive motor fault ndex LED faulty ndex detector fault ndex LED index detector installation faulty PCB motor on circuit PCB index detection circuit See Item 1 PCB disk change ready Media in Media out ciuciit Track 0 assembly PCB track 0 detection failure See item 1 See Item 2 Head load solenoid PCB
22. ssembly Removal and Installation Installation 1 Remove the head carriage assembiv as 1 Remove the PCB as described in section 12 1 described in section 12 9 2 Remove the one pig tail clamp mounting screw 2 Remove the two stepper motor assembly 3 Remove the two guide rod clamp mounting mounting screws screws 3 Remove the stepper motor and stepper motor 4 Remove the head carriage assembly guide rod stopper clamp guide rod and pig tail clamp 4 Reverse the above procedure to reinstallation 5 Pull out the guide rod from the head carriage 5 After reinstallation adjust the radial alignment assembly and track 0 sensor as described in section 9 6 6 Reverse the above procedure to reinstall and 9 9 7 After reinstallation adjust the radial alignment and track 0 sensor as described in section 9 6 Stepper Motor Assembly and 9 9 Head Carriage Assembly Guide Rod Clamp Stepper Motor Stopper Fig 12 8 Stepper Motor Assembly Removal Fig 12 9 Head Carriage Assembly Removal 18 Pig tail leading Pig Tail Clamp 1 Pass the pig tail through the pig tail clamp See Fig 12 9 1 2 Locate the side 0 to the outer side and side 1 to the inner side provide a clearance of 1mm between them and place them parallel to each other Avoid twisting or closing 3 Fig 12 9 2 When the carriage is on the outer most track a When the head carriage is on the outer most track lead the side 0 and s
23. t level Resolution 4 Radial Alignment 6 Azimuth a rado 9 Asymmetry Head load time MINI B type Drive motor is fixed speed type 360 rpm Parameter Indexperiod Output level Modulation 4 Resolution Radial Alignment 6 Azimuth Index burst fa E Head load time 9 ADJUSTMENTS AND VERIFICATIONS 9 1 Motor Speed Verification Index Period 1 Insert a diskette run the motor and clamp Refer to the index period column of Table 8 1 2 Step to the specified track 3 Connect a frequency counter to the INDEX signal TP7 4 Check that the freguency counter readings meet the specifications of Table 8 1 9 2 Write Protect Verification 1 Check that the exerciser s write protect lamp goes on and off as a diskette is inserted and removed as specified in the table below Diskette with write protect Diskette with write protect hole open hole closed Not write protected write protected 9 3 Head Output Verification Use a new diskette if possible to identify head failure for this check 1 Insert a good diskette 2 Runthe motor 3 Stepto the track specified in the output level column of Table 8 1 4 Connect the oscilloscope probe as specified below Invert channel 2 and select the Add mode Set vertical deflection to 10 mV division and horizontal deflection to 20 ms division 5 Write 2F all 1 s on the entire circumference 6 Check tha
24. t the average output level meets the specifications of Table 8 1 _ Vmax Vmin Vaverage If it does not meet the specifications refer to Item 7 of the Trouble Analysis Table 9 4 Output Modulation Verification 9 5 9 6 Modulation is calculated by the following formula max 7 Vmin Modulation Amae Vin x 100 Vmax Vmin Using the value obtained in section 9 3 and check that the calculated value meets the specifications of Table 8 1 Maximum voltage Value Vmax Average Voltage Minimum Voltage Value Vmax Fig 9 1 Modulation Resolution Verification 1 Leavethe oscilloscope in the same condition as mentioned in section 9 3 2 Resolution is calculated by the following formula Resolution V2raverage x 100 Vif average 3 Check that the calculated value meets the specifications of Table 8 1 Radial Alignment Verification and Adjustment Introduction This adjustment is normally not necessary If the mounting screws for the stepper motor loosen or if parts become defective or if a compatibility error occurs check and readjust according to the following procedure Steps 4 to 9 below should be performed regardless of the type CE or DAD alignment diskette used Use an alignment diskette suitable to the type of FDD to be adjusted according to Table 3 1 1 Insert Panasonic alignment diskette CAUTION Be sure to leave the alignment diskette under room conditions for 20 minutes before adjustme
25. tor 1 R44 JERGISJISIV Metal Film Oxide Resistor T R45 ERJ6GEYJ104V _ Chip Resistor 11 R JERIGGEVOROOV ChipResistor 11 fo R47 48 ERJGGEYJ471V 7 ChipResistor 2 1 R9 _ ERJ6GEYI822V ChipResistor 1 D R50 51 ERJ6GEYJ393V ChipResistor jp 2 1 R52 53 ERJGGEYJ182V ChiprResistor 2 1 j IR54 ERI6GEYI221V ChipResistor J 3 o R55 ERJ6GEYJ273V chipResistor 11 1 T R56 OO ERJ6GEYJ473V _ ChipResistor TA 1 T R7 ERJ6GEYJ392V__ ChipResistor 1 1 R58 JERIGGEYG2O3V chipResistor TT fo T R59 60 ERJ6GEYJ102V ChipResistor 2 J j R61 ERJGGEYJAR7V _ ChipResistor 1 1 TT P R62 63 ERJ6GEYI392V Chipresistor 2 T VRI PK502H203HOD Variableresistor 1 J XL IEFO GC3205C4 _ Resonatg LIA KEK A 5365 16 SCHEMATIC DIAGRAM JU 475 4AGG TPS SIDE R W2 T m 5VA iew 1 com y2 39K 33K pc s L2 wi G PL Oo 8 0 FERRITE col D svoc 4 ME gt ERASE 2 0 01U ie RAS C110 022p cz Ra III MEE i P 8 2K AT 334 v GND Vg D lt 2 523 ka 3 iks So Bis C12 0 022 R53 1 8K 5V RETURN Y pek gt 6 MAIS MA157 c SIDE 1 R w2 Y C M 78 GEE C8 820P 12V RETURN P sk SER ESKA WRP SEE sv Es WY CAL 0 01 Mires EK RATI 100p R48 p R57 R13 12v oc 2 ERASE 74 DM EN 150 470 470 O 3 9K FISK jp 1 a Noe TENN Su VE TH
26. w times to find a Track 0 White good fit between the collet and the inside Track 0 Yellow diameter of the drive motor d Bind the screws of the cartridge guide e Check step c again if not good repeat step a through d until the correct center adjustment is achieved Stopper 1 Collet Assembly 12 4 Collet Assembly Removal Fig 12 3 Track 0 Sensor Assembly Removal 15 12 5 1 2 3 4 Clamp Assembly Removal and Installation Remove the front plate as described in section 12 2 Remove the shield plate as described in section 12 1 step 1 Remove the two clamp assembly mounting screws and take out the clamp assembiv Reverse the above procedure to reinstall Clamp Assembly Fig 12 5 Clamp Assembly Removal 16 12 6 1 2 3 4 5 6 7 8 Write Protect Sensor Assembly and Index Sensor Assembly Removal and Installation Remove the shield plate as described in section 12 1 step 1 Disconnect the J3 connector from PCB Draw out the pins of the write protect sensor assembly from the following locations on the J3 connector No9 11 At that time draw out the pins with lifting the stopper on the connector Draw out the pins of the index sensor assembly from the following locations on the J3 connector No5 7 At that time draw out the pins with lifting the stopper on the connector Remove the write protect sensor mounting screw
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Panasonic JU 475 4 Manual