SECTION 1
SERVICING NOTE
TABLE OF CONTENTSNOTES FOR REPAIRING
1. POWER (S101) Switch
The POWER switch is not for turning ON/OFF the power
Specifications ...........................................................................source. Pay attention when repairing even the POWER 1
switch is turned off.
1. SERVICING NOTE.......................................................YThe states when turning of2f the POWER switch are as
follows.
2. GENERALa. Motors (M901, 902) will be stopped.
Features ..............................................................................b. Plungers (PM901 to 903) will be turned of3f.
Precautions .........................................................................c. Amplifier output will be cut-off by muting on.3
Operation Flow Chart ........................................................The above items from Oa� to Oc� are controlled by the4
Location and Function of Controls ....................................microcomputer which makes the pin 38 of IC1095
Preparation .........................................................................(microcomputer) become Low level. 6
Dictating.............................................................................2. Be careful the short circuit when repairing since the power7
Transcribing .......................................................................supply circuit does not have any protection devices.9
Erasing .............................................................................Please note that the current shut down (D108) will be work11
Alarm System ..................................................................when the power connected to the opposite way12.
Telephone Recording .......................................................3. Crack of Flywheel Gear and Cam Gear12
Do not turn the Flywheel counterclockwise.
3. DISASSEMBLYThe flywheel gear and cam gear may be crack when turn the
3-1. Cabinet (Rear) Assy , Cabinet (Front) ASSY ...........flywheel counterclockwise.13
3-2. Main Board, Connecter (12P) Board ........................ 13
3-3. LED Board................................................................ 14
cam gear
3-4. Mechanism Deck ...................................................... 14
3-5. Servo Board, OHead Magnetic (REC/PB/Erase)
(HRP901)�, Motor (F/R) ASSY (M902).................. 15
3-6. Belt (FWD), Belt (F/R)............................................. 15
3-7. Motor (FWD) ASSY(M901) .................................... 16
4. MECHANICAL ADJUSTMENTS..........................17
5. ELECTRICAL ADJUSTMENTS............................18
6. DIAGRAMSflywheel
6-1. Explanation of IC Terminals.....................................motor (FWD) (M901)19
6-2. Block Diagram.......................................................... 21
6-3. Printed Wiring Boards (Servo Section) .................... 23
6-4. Schematic Diagram (Servo Section)......................... 25
6-5. Printed Wiring Boards (Main Section) ..................... 28
6-6. Schematic Diagram (Main Section) ......................... 31
7. EXPLODED VIEWS
7-1. Cabinet Section ......................................................... 35
7-2. Mechanism Deck Section (1) (MB-87-59) ............... 36
7-3. Mechanism Deck Section (2) (MB-87-59) ............... 37
8. ELECTRICAL PARTS LIST............................. 38
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH
MARK 0ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS
LIST ARE CRITICAL TO SAFE OPERATION.
REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE
PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN
SUPPLEMENTS PUBLISHED BY SONY.
Notes on chip component replacement
Y Never reuse a disconnected chip component.
Y Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
� 2 � |
ACEC
