XR-4900 - Sony Car Audio Service Manual (repair manual). Page 2

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Location of Controls .......................................................

3

Resetting the Unit ...........................................................

4

Detaching the Front Panel ...............................................

4

Setting the Clock .............................................................

4

Installation .......................................................................

5

Connections .....................................................................

6

.........................................................

9

............ 11

....................... 14

Test Mode ........................................................................ 14
Tape Deck Section .......................................................... 14
Tuner Section .................................................................. 15

................................................................. 18

6-1. Printed Wiring Board  –MAIN Section– ........................ 19
6-2. Schematic Diagram  –MAIN (1/2) Section– .................. 21
6-3. Schematic Diagram  –MAIN (2/2) Section– .................. 23
6-4. Printed Wiring Board  –PANEL Section– ...................... 25
6-5. Schematic Diagram  –PANEL Section– ......................... 27
6-6. IC Pin Function Description ........................................... 31

................................................ 33

............................... 36

• Keep the temperature of the soldering iron around 270 ˚C dur-

ing 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.

• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-

aged by heat.