Nakamichi 550 Service Manual

Page 1

Service Manual

Nakamichi

Nakamichi
550

2 Head Cassette System

Nakamichi 550

3/6433?in St" Gama SW

Page 2

CONTENTS

P.

N95.

11.
12.

General ........................................................................... 2
Principle of Operation ............................................................... 2
2. 1_ Tape Alarm and Shut-off Circuit ................................................ 2
2. 2, Solenoid Driver Circuit ....................................................... 3
2, 3. DC-to-DC Converter .......................................................... 3
2, 4_ Motor Governor ............................................................. 4
Cabinet Disassembly Instructions ....................................................... 5
Mechanical Adjustments ............................................................. 6
4. 1. Take-up Torque and Rewind Torque Adjustment ----------------------------------- 6
4. 2. Record/Playback Head Height Adjustment and Azimuth Alignment --------------------- 6
4, 3, Tape Speed Adjustment ...................................................... 6
4. 4. Automatic Push Button Release Adjustment ---------------------------------------- 6
4.5. Belt Travelling Adjustment ..................................................... 7
4_ 6. Flywheel Adjustment ......................................................... 7
4, 7_ Lubrication ................................................................ 7
Electrical Adjustments ............................................................... 3
Parts Location for Electrical Adjustment ................................................. 10
Mounting Diagrams and Parts List ...................................................... 12
7I 1I Main PCB Assy (SX) ....................................................... 12
7. 2. Dolby P.C.B. Assy ........................................................... 13
7I 3. RecI CalI PCB Ass'y ......................................................... 13
7_ 4, Switch P.C.B. Ass'y .......................................................... 14
7. 5. Volume P.C.B. Assy .......................................................... 15
7.6. 400 Hz OSC. P.C.B. Assy ..................................................... 15
7. 7. Headphone AMPI P_C_B_ Ass'y .................................................. 15
7, 8_ Solenoid Driver P.C.B. Assy ................................................... 16
7. 9. Alarm B P.C.B. Assy ......................................................... 17
7I1OI MicI AMPI P.C.B. Ass'y ....................................................... 17
7_ 11I Jack P.C.B. Assy ............................................................ 18
7. 12 Lamp P.C.B. Assy ............................................................ 19
7I 13. Car Battery PICIBI Assy ...................................................... 19
7.14. DD, MHX P.C.B. Ass'y ........................................................ 19
Mechanism Assy and Parts List ........................................................ 21
8. 1I Solenoid Holder Ass'y ......................................................... 21
8. 2. Head Base B Assy ........................................................... 21
8. 3. Mechanism Bracket L Ass'y and Mechanism Bracket R Ass'y -------------------------- 21
8. 4 Auto Shut-off Ass'y .......................................................... 21
8. 5_ MHX Motor Assy ........................................................... 21
8. 6. Flywheel Holder Ass'y C ...................................................... 22
8. 7_ Motor Cover Assy C .......................................................... 22
8_ 8 Transport Mechanism 1 ....................................................... 23
8. QI Transport Mechanism 2 ....................................................... 25
8. 10. Chassis .................................................................... 27
8. 11 Cabinet .................................................................... 29
Block Diagram ..................................................................... 3]
Schematic Diagrams ................................................................. 32
1OI1I Amplifier .................................................................. 32
10. 2_ Mechanism ................................................................. 33
Specifications ...................................................................... 33
History on 550 ..................................................................... 34
12I 1I Major Modifications .......................................................... 34
12I 2 Modification (details) ......................................................... 34