Nakamichi 480 Z Service Manual

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CONTENTS
1. General ...................................................................... 3
2. Removal Procedures ............................................................. 4
2. 1 Cassette Case Cover Assy .................................................. 4
2. 2 Top Cover Ass'y ........................................................ 4
2. 3 Bottom Cover Ass'y ..................................................... 4
2. 4. Front Panel Ass'y ....................................................... 5
2. 5. Headphone Jack Assy .................................................... 5
2. 6 Mechanism Assy ....................................................... 5
2. 7 Level Indicator Assy, Lamp P.C.B. Assy and Indicator P.C.B. Assy ..................... 5
2. 8 Logic P.C.B. Assy, Headphone Switch P.C.B. Ass'y and MPX Filter Switch P.C.B. Assy ........ 5
2. 9. Main P.C.B. Ass'y ....................................................... 5
2. 10. Control Switch Holder Ass'y ................................................ 6
2. 11. Switch P.C.B. Ass'y ...................................................... 6
2. 12. Volume P.C.B. Ass'y and Control Switch P.C.B. Assy ............................... 6
2. 13 Rear Panel Ass'y, Power Transformer and Power Switch ............................. 8
2. 14. Cassette Case Ass'y and Cover Plate Ass'y ....................................... 8
2. 15. Tape Counter Assy ...................................................... 8
2. 16. Capstan Motor Ass'y and Flywheel Assy ....................................... B
2. 17. Sub Mechanism Chassis Assy ............................................... 9
2. 18. Control Motor Ass'y and Reel Motor Assy ...................................... 9
2. 19. Cam Control Volume .................................................... 9
2. 20. Reel Hub Assy and Idler Assy .............................................. 9
2. 21. Cam Drive Gear and Control Cam ............................................ 10
2. 22. Head Mount Base Assy ................................................... 10
2. 23. Pressure Roller Ass'y and Erase Head .......................................... 10
2. 24. Record/Playback Head Assy ............................................... 10
3. Measurement Instruments ......................................................... 11
4. Mechanical Adjustments .......................................................... 11
4. 1. Mechanism Control Cam Adjustment .......................................... 11
4. 2 Tape Speed Adjustment ................................................... 12
4. 3 Record/Playback Head Tilt Adjustment ........................................ 13
4. 4. Head Base Stroke Adjustment ............................................... 14
4. 5. Tape Guides Adjustment and Erase Head Stroke Adjustment .......................... 14
4. 6 Erase Head Height and Tilt Adjustment 15
4. 7 Back Tension Adjustment ................ 15
4. 8. Record/Playback Head Height Adjustment and Azimuth Alignment ...................... 16
4. 9. Tape Travelling Adjustment ................................................ 17
4. 10. Record Switch Linkage Adjustment ........................................... 17
4. 11. Flywheel Holder Adjustment ............................................... 18
4. 12. Eject Wire Adjustment .................................................... 18
4. 13. Lubrication ........................................................... 18
5. Parts Location for Electrical Adjustment ................................................ 19
6. Electrical Adjustments and Measurements ............................................... 20
6. 1. Adjustment and Measurement Instructions ...................................... 20
6. 2. Playback Frequency Response Adjustment ...................................... 23
6. 3. Dolby NR Circuit Check .................................................. 24
7. Mounting Diagrams and Parts List .................................................... 25
7. 1. Main P.C.B. Ass'y ....................................................... 25
7. 2. Volume P.C.B. Assy ..................................................... 31
7. 3. Lamp P.C.B. Assy ...................................................... 31
7. 4. MPX Filter Switch P.C.B. Ass'y .......... 31
7. 5. Headphone Switch P.C.B. Ass'y .......... . 31
7. 6. Bias Tune Volume P.C.B. Ass'y .............................................. 31
7. 7. Indicator P.C.B. Ass'y .................................................... 31
7. 8. Switch P.C.B. Ass'y ...................................................... 31
7. 9. Shut-off P.C.B. Assy ..................................................... 32

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1. GENERAL

1.1. Control Functions
The Nakamichi 4802 control functions are shown below:

Fig. 1.1 Front View

Fig. 1.2 Rear View

1. Power Switch 10. Record Button 19. Eq. Switch

2. Cassette Lid 11. Rewind Button 20. MPX Filter Switch

3. Eject Button 12. Stop Button 21. Input Jacks

4. Counter Reset Button 13. Play Button 22. Headphone Level Switch
5. Tape Counter 14. Fast~Forward Button 23. Output Jacks

6, Input Level Controls 15- Pause Button 24. Remote Control Socket
7. Peak Level Meters 15- Tape Memory SWiTCh 25. Voltage Selector Switch
8. Headphone Jack 17. Tape Selector SWitCh 26 Power Cord

9. Bias Tune Control 18- Dolby NR SWitCh

1.2. Voltage Selector
Voltage Selector is installed on the rear panel for Other Version of the Nakamiohi 4802.
This voltage selector can select either 120 V or 2207240 V at customer's disposal.

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sggif'E-ff Part No. Description savings: Part No. Description
BAO4512A Logic P.C.B. AS'Y R420,433 0305615A Carbon Resistor 22K ERD-ZST J
Serial Nos A30801001 - A30808687 434,435
Serial Nos: A30901001 A30908912 435,472
473,484
OBO7964C Logic P.C.B. 492.496
"3401 03061243 IC RC4558D 498'504
0401,4011 0306013A Transistor 25A733 R423 0301684A Carbon Resistor 470K ERD-25T J
405,407 R437,493 0501682A Carbon Resistor 6.8K ERD-25T J
409.412 R438,450 0805692A Carbon Resistor 68K ERD-25T J
414,415 R440 0501683A Carbon Rasistor 15K ERD-25T J
418.424 R442,463 0305508A Carbon Resistor 56K ERD»25T J
434 R443,483 OBOSGZZA Carbon Resistor 2,2K ERD-ZST J
0402.413 DBOSOGQA Transistor 253564 499
425,428 R445,446 OBOlGSiA Carbon Resistor 3.3K ERD-25T J
0403,406 0B06100A Transistor 2SC945 (A) 455430
403.410 R452 0309314A Carbon Resistor 5.1 K ERD-25T J
411.417 R453 0509384A Fail Safe Type Resistor 27 RDF-ZSS J
419.422 R459 0601680A Carbon Rasistor 820 ERD-ZST J
426,432 R464 0309340A Metal Film Resistor 15K SN14K2E F
433 R466 OBOQ32SA Metal Film Resistor 9,1K SN14K2E F
0416 0806251A Transistor 250945 (0) 8467.469 0305671A Carbon Resistor 2.2M ERD-25TJ
0420.427 OBOGOGGA Transistor 280471 R470 0309214A Fail Safe Type Resistor 1 HDF-zss J
0421 OBOGZSZA Transistor 253564 (Kl R494 0305626A Carbon Resistor 150K ERD-25T J
0423 0306155A Transistor 2SA733 (Pl R497 oeosezaA Carbon Resistor 1.2K ERDA25T J
0429 OBOGOZOA Transistor 25C1096 c401 0309345A Electrolytic Capacitor 33;; 25v (BP)
0430 0306012A Transistor ZSA634 0402.403 0509332A Electrolytic Capacitor 2.2;: 25v (LN)
D401423 0306181A Silicon Diode 15553 (33 pcs.) 417
429-433 C404 0509333A Electrolytic Capacitor 4.7;: 25V (LN)
4354139 C405 0301272A Electrolytic capacitor 100; 25V
R401,403 0501889A Carbon Resistor 100K ERD-25T J C406 0501405A Electrolytic Capacitof 1 50V
407,409 C407 0501674A Electrolytic Capacitor 10y 25V
414.421 €408,411 0309290A Ceramic Capacitor 0.01M 50V 2
426,429 413
430,432 C409 0809251A Electrolytic Capacitor 33 25V
441,447 C410 0309283A Ceramic Capacitor 220P 50V K
448,456 C412 0309292A Ceramic Capacitor 0.1;: 50V Z
457,462 C414 0801676A Mylar Capacitor 0.056;; 50V
465,458 6416 OBOQSSBA Electrolytic Capacitor 22;; 25V (BPl
474,475 C418 DBOMOZA Electrolytic Capacitor 47;: 25V
476,489 C419 0309277A Ceramic Capacitor 10F 50V J
490 CNl 0308681A 12P-T Post
R402,415 OBO1888A Carbon Resistor 10K ERD-ZST J CN2 OBOSGSBA 3P-T Post
416,422 OBOSSOSA Transistor Mica TO-202 (1 Dee.)
451,471 0808607A Transistor Bushing T0202 (1 race.)
482,485 0E00507A Nut Hex. M3 (1 Deer)
486,487 0E00510A Sorew M3X8 Philips Pan Head (2Al
488 (1 race.)
R404,406 0B01887A Carbon Resistor 5.6K ERD-ZST J 0E00857A BT Screw M3x6 Philips Binding Head
412 (4 pcs.)
R405,413 0805575A Carbon Resistor 560 ERD-25T J 0J04349A P.C.B. Holder L (1 pce.)
R408,424 0505627A Carbon Resistor 330K ERD-25T J 0JO4350A P.C.B. HoldEr R (1 pce.)
425,427
444,449
461,495
R410,439 OBOQSSSA Carbon Resistor 680K ERD-25T J
R411 0505621A Carbon Resistor 120K ERD»25T J
R417,431 0801846A Carbon Resistor 4.7K ERD-ZST J
R418,454 OBO1857A Carbon Resistor 1K ERD-ZET J
458.500
501
R419,491 0805509A Carbon Resistor 33K ERD-ZST J

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8.2. Front Panel Assy (A01)

8.3. Synthesis Mechanism Ass'y (A02)

05

O4 02

Fig. 8.3

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