Nakamichi 482 Service Manual

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Service Manual

Nakamichi

Nakamichi
482

Discrete Head Cassette Deck

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CONTENTS

1. General ....................................................................... 3
2. Principle of Operation ............................................................. 4
2. 1. Mechanisms ............................................................ 4
2.1.1 . Headblock ...................... 4
2.1.2. Erase Head ..................... 5
2.1.3. Double Capstan Tape Drive .......... 5
2.1.4. Mechanism Control Cam Operation .......................................... 6
2. 2. Amp. Circuits .......................................................... 7
2.2.1. Playback Eq. Amp. Circuit ............................................. 7
2.2.2. Record Eq. Amp. Circuit ............ 9
2.2.3. Bias Osc. Circuit ......................... 9
2. 3. Mechanism Control Circuits ................................................. 10
2.3.1. Outline. . .1 .......................................................... 10
2.3.2. +12 V Power Source .................................................... 11
2.3.3. magma ..................................................... 11
2.3.4. Auto Shut-off Circuit
2.3.5. Record Control Circuit
2.3.6. Mute Signal ............................................. . ............. 14
2.3.7. Control Motor Drive Circuit ............................................... 15
2.3.8. Reel Motor Governor ................................................... 16
3. Removal Procedures ................................ 17
3. 1. Cassette Case Cover Assy ..................... 17
3_ 2. Top Cover Ass'y ........................... 17
3. 3. Bottom Cover Ass'y ...................................................... 17
3. 4. Front Panel Assy ........................................................ 17
3. 5. Headphone Jack Ass'y ....................... 17
3. 6. Mechanism Ass'y .......................... 17
3. 7. Meter Ass'y .............................. . . 17
3. 8. Lamp P.C. B. R Ass'y and Lamp P.C.B. L Assy ..................................... 17
3. 9. Main P.C.B. Ass'y ........................................................ 17
3. 10. Control Switch Holder Assy ................... 17
3. 11. Switch P.C.B. Ass'y ......................... 17
3. 12. Volume P.C.B. Ass'y and Control Switch P.C.B. Assy . . . . . . 17
3. 13. Rear Panel Assy, Power Transformer and Power Switch .............................. 17
3. 14. Cassette Case Ass'y and Cover Plate Ass'y ........................................ 19
3. 15. Tape Counter Assy ....................................................... 19
3. 16. Capstan Motor Assy and Flywheel Assy ........................................ 20
3. 17. Sub Mechanism Chassis Assy ...........
3. 18. Control Motor Assy and Reel Motor Assy . .
3. 19. Cam Control Volume ................ . .
3. 20. Reel Hub Assy and Idler Ass'y ............................................... 20
3. 21. Cam Drive Gear and Control Cam .............................................
3. 22. Head Mount Base Ass'y ...............
3. 23. Pressure Roller Assy and Erase Head ......
3. 24. Playback Head Assy and Record Head Ass'y .
4. Measurement instruments ..........................................................
5. Mechanical Adjustments ...........................................................
5. 1. Mechanism Control Cam Adjustment .......................
5. 2. Tape Speed Adjustment ................................
5. 3. Record Head and Playback Head Tilt Adjustment ...............
5. 4. Head Base Stroke Adjustment ................................................ 24
5. 5. Tape Guides Adjustment and Erase Head Stroke Adjustment ........................... 25
5. 6. Erase Head Height and Tilt Adjustment ......................................... 25
5. 7. Playback Head and Record Head Height Adjustment and Azimuth Alignment ................ 27
5. 8. Record Head Stroke AdJ'UStment .............................................. 28
5. 9. Tape Travelling Adjustment ................................................. 29

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9.10.

Sub Mechanism Chauis Ass'y (002)

Fig. 9.10
8:2:- "11:3: Part No. Description O'ty
(:02 CA08155A Sub Mechanism Chassis Assy 1
01 06080393 Reel Hub Head 2
02 CA080383 Reel Hub B Ass'v 2
O3 CA08037A Reel Hub Take-up Assy 1
04 CAD8064A Reel Hub Supply Ass'y 1
05 CA08039A Back Tension Ass'v 1
06 0008178A Back Tension Spring 1
07 CA08040A Idler Assy 1
08 08081273 Idler Arm Spring 1
09 CAOSD42A Brake Arm Ass'y 2
10 OCOSOSOC Brake Drive Arm 1
11 0C08029A Brake Arm Spring 1
12 0C08128A Brake Drive Arm Spring 1
13 CA08117B Heel Motor Ass'y 1
14 CA08124A Control Motor Ass'y 1
15 00080533 Volume Coupler 1
16 OBO7240A Volume Control 10kn (B) 1
17 cA08041 A Sub Chassis Ass'y
L01 OEOOEAZA Stopper Ring 2mm 1
L02 0E00837A Stopper Fling 3mm 2
L03 0E00838A Stopper Fling 4mm _ 1
L04 0E00859A BT Screw M2.6x6 Philips Binding 1
Head
L05 0E00226A Screw M2.6x4 Philips Pan Head 5
L06 - Volume Nut (1),
L07 - Volume Washer (1)

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Sigma-[WEE > Part No. Description Oty
F04 CA081 21A Head Bees Ass'y C 1
01 GAOQO17A Ev8L Erase Head 1
02 0C081 58D EH Hold Plate 1
03 0008166A EH Hold Plate Spring 1
04 0008174C Cassette Hold Spring 1
05 CAOSOOSP Head Base Assy 1
06 0C081 75A Head Base L Spring 3
07 013086790 2P-H Connector 1
L01 0E00889A Screw M1 .7x8 Philips Pan Head 2
L02 OEOOQOQA Screw M2x6 Philips Pan Head 3
L03 0E001 1 7A Washer 2mm 3
L04 OEOO853A BT Screw M2x3 Philips Pan Head 1
F05 CA08141A Cassette Case Holder L Asv 1
01 06080730 Lid Arm A 1
02 0C0811 4A Lid Arm Spring 1
03 CAOSOQOF Cassette Case Holder L Sub Assv 1
L01 0E00837A Stopper Hing 3mm 1
F06 CAOSOZZA Cassette Case Holder R Ass'y 1
01 0608133A Eject Sansor 1
02 CAOSOMA Cassette Case Holder Fl Sub Assy 1
L01 0E00840A BT Screw M2x8 Philips Pan Head 2
F07 CA081 19A Auto Shut-off Assy 1
01 0008047A Shut-off Pulley A 1
02 OCOBZOSB Shut-off Pulley B 1
03 00080883 Shut~off Pulley Shaft 1
04 00082073 Shut-off Pulley Holder 1
05 BA041 28A Shut-off P.C.B. Assy 1
F08 CAOBO30A Pneumatic Damper Ass y 1
01 00080581: Damper Piston 1
02 00081023 Damper Ring 1
03 0C0801OC Damper Plate 1 >
04 0008059E Svlinder 1
L01 0E00874A Stopper Fling CS 2mm 1
(301 CA08137A PvBL Playback Head Assy 1
01 0008160F Head Plate 1
02 GA02034A P-8L Playback Head 1
03 0C081690 Pad Lifter 54 1
04 08087040 PH Con nectar 1
L01 0E00886A Screw Ml.7x6.5 Philips Pan Head 2
G02 CAO8138A R-SL Record Head Asy . 1
01 00081 596 Head Plate 1
02 GA01050A R-8L Record Head 1
03 03087058 RH Connector 1
L01 0E00887A' Screw M1 .7x4 Philips Pan Head 2

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