Sony XR-4890 Service Manual
XR-4890
SERVICE MANUAL
Photo: XR-4890
SPECIFICA TIONS
US Model
Canadian Model
Model Name Using Similar Mechanism XR-C5100
Tape T ransport Mechanism T ype MG-25F-136
MICROFILM
– Continued on next page –
FM/AM CASSETTE CAR STEREO
TABLE OF CONTENTS
1. GENERAL
Location of Controls ....................................................... 3
Resetting the Unit ........................................................... 4
Detaching the Front Panel............................................... 4
Setting the Clock ............................................................. 4
Installation....................................................................... 5
Connections ..................................................................... 6
2. DISASSEMBLY ......................................................... 9
3. ASSEMBLY OF MECHANISM DECK............11
4. MECHANICAL ADJUSTMENTS .......................14
5. ELECTRICAL ADJUSTMENTS
Tape Deck Section .......................................................... 14
Tuner Section .................................................................. 14
6. DIAGRAMS................................................................. 15
6-1. Printed Wiring Board –MAIN Section– ........................ 17
6-2. Schematic Diagram –MAIN (1/2) Section–.................. 19
6-3. Schematic Diagram –MAIN (2/2) Section–.................. 21
6-4. Printed Wiring Board –PANEL Section– ...................... 23
6-5. Schematic Diagram –PANEL Section–......................... 25
6-6. IC Pin Function Description ........................................... 27
7. EXPLODED VIEWS ................................................29
8. ELECTRICAL PARTS LIST ............................... 32
Flexible Circuit Board Repairing
• Keep the temperature of the soldering iron around 270 ˚C during repairing.
• Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
• Be careful not to apply force on the conductor when soldering
or unsoldering.
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be damaged by heat.
– 2 –
SECTION 1
GENERAL
This section is extracted from
instruction manual.
– 3 –
– 4 –
– 5 –
– 6 –
– 7 –
– 8 –
SECTION 2
1
1
1
2
2
2
3
cover ass’y
DISASSEMBLY
Note: Follow the disassembly procedure in the numerical order given.
FRONT PANEL ASS’Y
1
Push the button
(release).
2
Remove the front panel ass’y
to the direction of the arrow
A
A
.
COVER ASS’Y
– 9 –
SUB PANEL, MECHANISM DECK (MG-25F-136)
3
connector
(CN351)
2
sub panel
1
three screws
(PTT2.6
×
8)
5
screw
(PTT2.6
4
flexible flat cable
(CN301)
×
6)
6
mechanism deck
(MG-25F-136)
1
three screws
(PTT2.6
×
MAIN BOARD, HEAT SINK
3
Two ground point
screws
4
main board
8)
5
two screws
(PTT 2.6
2
rubber cap (25)
×
8)
5
two screws
(PTT 2.6
6
heat sink
×
10)
1
(PTT2.6
5
two screws
(PTT 2.6
screw
×
8)
×
8)
– 10 –
1
two screws
(PTT2.6
×
8)
Loading...