Tascam 133 Service Manual

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TASCAM

TEAC Production Products

SERVICE MANUAL

MULTI-IMAGE STEREO PLUS CUE
CASSETTE RECORDER-REPRODUCER

6704010700

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I33

TABLE OF CONTENTS

1 . Specifications ........................................................ 4
2. Description of Major Parts and Controls
2-1. Front Panel ..................................................... 6
2-2. Rear Panel ...................................................... 9
3. Circuit Description
@trol Section
3-1. System Control Outlined .......................................... 10
3-2. Multiplexer of Operating Key Signals ................................. 11
3-3. Multiplexer for AutoPresent Switches ................................ 12
3-4. Controller
3-4-1. Pin assignments ............................................... 14
3-4-2. Block diagram ................................................ 16
343 Control program and function addresses ............................ 16
3-44. Timing diagram ............................................... 17
35. Motor Reversing IC
3-5-1. Pin assignments ............................................... 18
3-5-2. Block diagram and truth table .................................... 18
3-6. Operation of the System Controller
36-1. Clock circuit .................................................. 18
3-6-2. Initial reset circuit ............................................. 20
3-7. Command Input Circuit ........................................... 20
3-8. Solenoid Drive Circuit
3-8-1. Fast solenoid drive circuit ....................................... 22
3-8-2. Held base solenoid drive circuit ................................... 23
3-8-3. Pinch roller solenoid drive circuit .................................. 24
3-9. Reel Motor Drive Circuit
3-9-1. Direction of motor rotation ...................................... 24
332. Motor drive circuit ............................................. 25
3-10. Capstan Motor Drive Circuit ........................................ 26
3-11. Tape Counter Circuit
3-11-1 . Tape counter ................................................. 27
Cue Signal Section
3-12. Cue Signal Reproducing Circuit ..................................... 29
3-13. Cue Signal Output Circuit ......................................... 30
3-14. Cue Signal Peak Level Meter Circuit .................................. 30
3-15. Cue Signal Recording Circuit ....................................... 31
3-16. Cue Signal (25 Hz) Generating Circuit ................. , ............... 32
3-17. Auto-Present Operation ........................................... 33
4. Essential Maintenance Equipment/Material ................................ 35
5. Check and Adjustment of the Mechanism
5-1. Head Base Plate Positioning ........................................ 36
5-2. Microswitch (A)Aseembly Clearance ................................. 36
5-3. Microswitch (B) Assembly Clearance ................................. 36
5-4. Capstan Assembly Thrust .......................................... 37
5-5. Takeup Torque ......................... ' ......................... 37
5-6. Fast Forward and Rewind Torque ................................... 37
5-7. Pinch Roller Pressure ............................................. 37
5-8. Tape Speed ..................................................... 38
5- 9. Wow and Flutter ................................................ 38
6. Check and Adjustment of the Record/Play Amplifier ........................ 39
6-1. Playback Level .................................................. 40
6-2. VU Meter Reading ............................................... 40
6-3. Playback Frequency Response ...................................... 40

6-4. Bias Dummy Coil Adjustment ...................................... 41