MDX-66XLP - Sony Car Audio Service Manual (repair manual)

1

Model Name Using Similar Mechanism

NEW

Mini Disc Mechanism Type

MG-798LP-133

Optical Pick-up Name

KMS-241C/J1N

US Model

Canadian Model

AEP Model

UK Model

System

Mini disc digital audio system

Frequency response

10 – 20,000 Hz

Wow and flutter

Below measurable limit

Signal-to-noise ratio

95 dB

Outputs

Bus control output (8 PIN)
Analog audio output (RCA PIN)

Current drain

300 mA (MD playback)
600 mA (during loading or
ejecting a disc)

Dimensions

Approx. 176 

×

 83.5 

×

 142 mm

(7 

×

 3 

3/8

 

×

 5 

18/32

 in.) (w/h/d)

not incl.
projecting parts and controls

Mass

Approx. 1.1 kg (2 lb. 7 oz.)

Power requirement

12 V DC car battery (negative
ground)

Supplied accessories

Mounting hardware (1 set)
Bus cable 5.5 m (1)
RCA pin cord 5.5 m (1)

2002D0400-1

© 2002. 04

• MDLP (MiniDisc Long Play) playback.
• Sony BUS system compatible with mobile MD

changers.

• Direct-in system for inserting and removing

MDs easily.

• The MD changer compartment has a built in light

for easy use even in the dark.

• 1 bit Digital/Analog converter for high quality

sound reproduction.

2

1-1.   To Place the Set into Playback Mode .................................. 3
1-2.   How to Check the Servo Board Waveforms ........................ 3

Preparations (US, Canadian Model) ........................................ 4
Connections (US, Canadian Model) ........................................ 4
Preparations (AEP, UK Model) ............................................... 5
Connections (AEP, UK Model) ............................................... 5

3-1.   Panel (Rear) Assy ................................................................ 6
3-2.   Case (Upper) ....................................................................... 7
3-3.   Panel (Front) Assy ............................................................... 7
3-4.   MD Block ............................................................................ 8
3-5.   Main Board ......................................................................... 8
3-6.   Chassis (OP) Block ............................................................. 9
3-7.   Servo Board ......................................................................... 9
3-8.   Optical Pick-up ................................................................. 10
3-9.   Note on Assembly for the Chassis (OP) Block ................. 11

4-1.   IC Pin Descriptions ........................................................... 12
4-2.   Block Diagram .................................................................. 18
4-3.   Circuit Boards Location .................................................... 19
4-4.   Printed Wiring Boards –Servo Section– ............................ 20
4-5.   Schematic Diagram –Servo Section– ................................ 22
4-6.   Schematic Diagram –Main Section– ................................. 23
4-7.   Printed Wiring Boards –Main Section– ............................ 24
4-8.   Printed Wiring Board –Power Section– ............................ 26
4-9.   Schematic Diagram –Power Section– ............................... 27

5-1.   Case Section ...................................................................... 30
5-2.   Main Board Section .......................................................... 31
5-3.   MD Section (1) .................................................................. 32
5-4.   MD Section (2) .................................................................. 33
5-5.   MD Section (3) .................................................................. 34

........................................ 35

0

0

0

Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous
radiation exposure.

laser-tap

•

Never reuse a disconnected chip component.

•

Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.

The laser diode in the optical pick-up block may suffer electrostatic
breakdown because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic breakdown and also use
the procedure in the printed matter which is included in the repair
parts.
The flexible board is easily damaged and should be handled with
care.

The laser beam on this model is concentrated so as to be focused on
the disc reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission, ob-
serve from more than 30 cm away from the objective lens.

The pick-up flexible board in this set is secured to the optical pick-
up with an adhesive tape. Once the tape is removed, an adhering
force becomes weak, and it cannot be reused.
Therefore, if the optical pick-up is replaced, replace also the pick-
up flexible board with a new one.

The laser diode in the optical pick-up block may suffer electrostatic
break-down easily. When handling it, perform soldering bridge to
the laser-tap on the flexible board. Also perform measures against
electrostatic break-down sufficiently before the operation. The
flexible board is easily damaged and should be handled with care.

CLASS

PRODUCT

LASER

1

This label is located on the bottom of the chassis.

3

The this set has no key control function and cannot be placed into
the Playback mode alone.
For key control, the this set is controlled through serial
communication with a master unit (car audio player, TV tuner or
source selector compatible with the Sony BUS system.)
To service the this set, the set should be connected as given below:

1. Remove the panel (rear) assy, case (upper) and panel (front) assy.

Then, remove the main board from the mechanism deck. (See
page 8 of “SECTION 3. DISASSEMBLY”.)

2. Remove the chassis (OP) block from the mechanism deck. (See

page 9 of “SECTION 3. DISASSEMBLY”.)

3. Short each bridge points BP1 and BP2 on the main board by

solder bridge.

4. Connect the power board with the main board by the main

flexible board. Connect the main board with the servo board by
the servo flexible board.

5. Connect to a master unit. With the master unit OFF, press the

preset buttons 4 

t 5 t 1 (2 seconds or more each) in this

turn to enter the TEST mode.

6. Open the doors and insert a disc in the chassis (OP) assy. Use the

 SOURCE  button on the master unit to select to MD to
playback.

7. Check the waveforms at each point on the servo board.

After this check is completed, remove solder between shorted
bridge points BP1 and BP2 and open these points.

MDX-66XLP

Master unit

BUS CONTROL IN

BUS CONTROL OUT

BP1

BP2

– main board (conductor side) –

4

This section is extracted
from instruction manual.