SONY MDS-JA50ES User Manual
MDS-JA50ES
SERVICE MANUAL
Photo: GOLD
Model Name Using Similar Mechanism NEW
MD Mechanism Type MDM-4A
Base Unit Type MBU-2B
Optical Pick-up Type KMS-210A/J-N
SPECIFICATIONS
US Model
AEP Model
UK Model
MICROFILM
MINIDISC DECK
— 1 —
CAUTION
SAFETY CHECK-OUT
After correcting the original service problem, perform the following safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, “metallized” knobs, screws,
and all other exposed metal parts for A C leakag e. Check leakage as
described below.
LEAKAGE
The AC leakage from any exposed metal part to earth Ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microampers). Leakage current can be measured by any one of three methods.
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers’ instructions to use these
instruments.
2. A battery-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for this job.
3. Measuring the voltage drop across a resistor by means of a V OM
or battery-operated A C v oltmeter. The “limit” indication is 0.75
V, so analog meters must have an accurate low-voltage scale.
The Simpson 250 and Sanwa SH-63Trd are examples of a passive VOM that is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are suitable. (See Fig. A)
To Exposed Metal
Parts on Set
Danger of explosion if battery is incorrectly replaced.
Replace only with the same or equivalent type recommended by
the equipment manufacturer.
Discard used batteries according to manufacture’s instructions.
ADVARSEL!
Lithiumbatteri - Eksplosionsfare ved fejlagtig håndtering.
Udskiftning må kun ske med batteri af samme fabrikat og type.
Levér det brugte batteri tilbage til leverandøren.
ADVARSEL
Eksplosjonsfare ved feilakting skifte av batteri.
Benytt samme batteritype eller en tilsvarende type anbefalt av
apparatfabrikanten.
Brukte batterier katterier kasseres i henhold til fabrikantens
VARNIG
Explosionsfara vid felaktigt batteribyte.
Använd samma batterityp eller en likvärdig typ som rekommenderas
av apparattillverkaren.
Kassera använt batteri enligt gällande föreakrifter.
VAROITUS
Parist voi räjähtää, jos se on virheellisesti asennettu.
V aihda paristo ainoastaan laite valmistajan suosittelemaan tyyppiin.
Hävitä käytetty paristo valmistajan ohjeiden mukaisesti.
0.15µF
1.5k
Ω
Earth Ground
AC
voltmeter
(0.75V)
Fig. A. Using an AC voltmeter to check AC leakage.
SAFETY-RELATED COMPONENT WARNING !!
COMPONENTS IDENTIFIED BY MARK ! OR DO TTED LINE
WITH MARK ! ON 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.
— 2 —
The laser component in this product is
capable of emitting radiation exceeding
the limit for Class 1.
This appliance is classified as a CLASS 1
LASER product. The CLASS 1 LASER
PRODUCT MARKING is located on the
rear exterior.
TABLE OF CONTENTS
1. SERVICING NOTE
.......................................................... 4
2. GENERAL .......................................................................... 7
3. DISASSEMBLY
3-1. Tray Assembly .................................................................... 26
3-2. Bracket (Motor) ASSY ....................................................... 27
3-3. Holder ASSY ...................................................................... 27
3-4. Base Unit.............................................................................28
3-5. HMOT Board and HLIM Board ......................................... 28
4. TEST MODE ..................................................................... 29
The following caution label is located
inside the unit.
CAUTION
Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous radiation exposure.
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.
Flexible Circuit Board Repairing
• Keep the temperature of 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.
MODEL IDENTIFICATION
— BACK PANEL —
Parts No.
5. ELECTRICAL ADJUSTMENTS ............................... 32
6. DIAGRAMS
6-1. Brock Diagrams
• BD Section ....................................................................... 37
• Digital Section ................................................................. 39
• Audio Section .................................................................. 41
• Power Section .................................................................. 43
6-2. Circuit Boards Location ...................................................... 44
6-3. Waveforms ......................................................................... 45
6-4. Printed Wiring Board — BD Section —.............................47
6-5. Schematic Diagram — BD Section — ............................... 49
6-6. Schematic Diagram — Digital Section —.......................... 52
6-7. Printed Wiring Board — Digital Section — ....................... 55
6-8. Printed Wiring Board — MD Section —............................ 57
6-9. Schematic Diagram — MD Section — .............................. 58
6-10. Printed Wiring Board — D Out, D Vol Section — .......... 59
6-11. Schematic Diagram — D Out, D Vol Section — ............. 60
6-12. Printed Wiring Board — DA Section — .......................... 61
6-13. Schematic Diagram — DA Section —.............................63
6-14. Printed Wiring Board — AD Section — .......................... 65
6-15. Schematic Diagram — AD Section —.............................67
6-16. Printed Wiring Board — Panel Section —....................... 69
6-17. Schematic Diagram — Panal Section — ......................... 71
6-18. Printed Wiring Board — Power Section — ..................... 73
6-19. Schematic Diagram — Power Section — ........................ 75
6-20. IC Block Diagrams ........................................................... 77
6-21. IC Pin Functions ............................................................... 84
7. EXPLODED VIEWS
7-1. Main Section ..................................................................... 100
7-2. Chassis Section ................................................................. 101
7-3. Front Panel Section 1 ........................................................ 102
7-4. Front Panel Section 2 ........................................................ 103
7-5. Mechanism Section 1 (MDM-4A) .................................... 104
7-6. Mechanism Section 2 (MDM-4A) .................................... 105
7-7. Mechanism Section 3 (MDM-4A) .................................... 106
7-8. Base Unit Section (MBU-2B) ........................................... 107
4-987-511-2 : AEP, UK, German model
4-987-511-3 : US model
8. ELECTRICAL PARTS LIST ...................................... 108
— 3 —
SECTION 1
SERVICING NOTE
HOW TO OPEN THE DISC TRAY WHEN POWER SWITCH TURNS OFF
1 Remove the fourteen screws (BVTT 3x8) from the bottom plate.
2 Remove the bottom plate.
3 Rotate the pulley gear in the arrow direction A, and open the tray assembly in the arrow direction B.
Pully gear
A
B
Tray assembly
FORCED RESET
The system microprocessor can be reset in the following way.
Use these methods when the unit cannot be operated normally due to the overrunning of the microprocessor, etc.
Method 1:
Set TP (S.RST) of the DIG board to ground momentarily.
[DIG board] (Side A)
CN203
TP
(S.RST)
C206
IC202
Method 2:
Disconnect the power plug, and short-circuit CN905 of the PW board
with a pair of tweezers, etc.
[PW board] (Component Side)
CN901
CN905
(RESET)
— 4 —
RETRY CAUSE DISPLAY MODE
• In this test mode, the causes for retry of the unit during recording can be displayed on the fluorescent display tube.
This is useful for locating the faulty part of the unit.
• The retry cause, number of retries, and number of retry errors are displayed. Each is displayed in hexadecimal number.
Method:
1. Load a recordable disc whose contents can be erased into the unit.
2. Press the p button, §OPEN/CLOSE button, DISPLAY/CHAR button simultaneously.
3. Press the r button, and start recording.
4. The ## value increases with each retry. If an error occurs after a retry, the @@ count will also increase.
5. To exit the test mode, press the TIME button.
Fig. 1 Reading the Test Mode Display
R.T s ∗ ∗ c # # e @@
Fluorescent Display Tube Signs
∗ ∗ : Cause of retry
# # : Number of retries
@@: Number of retry errors
All three displays above are in hexadecimal numbers.
— 5 —
Reading the Retry Cause Display
Higher Bits Lower Bits
Hexadecimal
Bit
Binary
*1 Some displays are not used depending on the microprocessor version.
Reading the Display:
Convert the hexadecimal display into binary display. If more than two causes, they will be added.
Example
When 42 is displayed:
Higher bit : 4 = 0100 n b6
Lower bit : 2 = 0010 n b1
In this case, the retry cause is combined of “spindle is slow” and “ader5”.
84218421
b7 b6 b5 b4 b3 b2 b1 b0
00000001
00000010
00000100
00001000
00010000
00100000
01000000
10000000
Hexa-
decimal
01
02
04
08
10
20
40
80
Cause of Retry Occurring conditions
shock *1
ader5
Discontinuous address
(Not used)
FCS incorrect
IVR rec error
Spindle is slow
Access fault
When more than 3.5 shocks are detected
When ADER was counted more than
five times continuously
When ADIP address is not continuous
(Not used)
When not in focus
When ABCD signal level exceeds the specified range
When spindle rotation is detected as slow
When access operation is not performed normally
When A2 is displayed:
Higher bit : A = 1010 n b7+b5
Lower bit : 2 = 0010 n b1
The retry cause in this case is combined of “access fault”, “IVR rec error”, and “ader5”.
Hexadecimal n Binary Conversion Table
Hexadecimal Binary Hexadecimal Binary
0
1
2
3
4
5
6
7
Reference:
In this test mode, when the · button is pressed, and the disc is played back, the “PLAYBACK MODE” is set.
The display becomes as shown in Fig. 2. The playback mode is not used in particular during servicing.
44 ¢¢¢¢¢¢ p
0000
0001
0010
0011
0100
0101
0110
0111
8
9
A
B
C
D
E
F
1000
1001
1010
1011
1100
1101
1110
1111
Fig. 2 Display during Playback Mode
4 : Parts No. (Name of area named on TOC)
¢¢¢¢¢¢ : Address (Physical address on disc)
p : Track mode (Copyright information of each part, information on copyright, etc.)
— 6 —
Location of Parts and Controls
SECTION 2
GENERAL
12
@¢
1 POWER switch
2 Remote sensor
3 TIMER switch
4 FILTER button
5 SCROLL/CLOCK SET button
6 DISPLAY/CHAR button
7 Disc tray
8 0/) (fast backward/fast forward) buttons
9 EDIT/NO /YES buttons
Pressing the EDIT/NO button once, it becomes the edit menu
and the recorded disc can be programmed.
Pressing it twice it becomes the set up menu (page 43), and
various settings are possible.
34567
@£
@™
@¡
@º
890
!•!ª
!º AMS knob
!¡ DIGITAL REC LEVEL knob
!™ ANALOG REC LEVEL L/R knob
!£ r REC (recording) button
!¢ p (stop) button
!∞ P (pause) button
!§ ( (play) button
!¶ § OPEN/CLOSE button
!• Display window
!ª TIME button
@º REPEAT button
@¡ PLAY MODE button
@™ INPUT switch
@£ PHONE LEVEL knob
@¢ PHONES jack
!¶
!§
!¡ !™
!∞
!£!¢
— 7 —
This section is extracted from
instruction manual.
— 8 —
— 9 —
— 10 —
— 11 —
— 12 —
— 13 —
— 14 —
— 15 —
— 16 —
— 17 —
— 18 —
— 19 —
— 20 —
— 21 —
— 22 —
— 23 —
— 24 —
— 25 —
SECTION 3
DISASSEMBLY
Note : Follow Xthe disassembly procedure in the numerical order given.
3-1. TRAY ASSEMBL Y
2
Two screws
(BVTP 3x6)
3
Two screws
(BVTP 3x6)
Bracket
4
(TOP)
A
5
Two gear
(Gear 4)
7
Screw
(BVTT 3x6)
8
Stopper
(Shaft A)
9
6
Two gear
(Gear 4)
Shaft
1
Rotate the pulley gear in the arrow
direction
assembly.
A
, and pull out the tray
0
Remove the tray assembly
in the arrow direction
• Precautions on Attaching
(Assemble in the reverse order of removal.)
Slider assembly
When attaching the tray assembly, first move the slider
assembly in the arrow direction
position shown.
Pin
B
B
A
B
and set Pin A at the
Bracket (TOP)
.
Note:
When attaching the bracket (TOP), attach while
pressing the switch as shown in the figure.
B
When attaching gear 4 (two in front), pull the tray
assembly in arrow direction
position racks (L), (R) and (D) as shown in the
figure.
A
completely, and
Rack (L)
A
Hole
Rack (D)
Gear 4
— 26 —
3-2. BRACKET (MOTOR) ASSY
1
Two screws
(BVTT 3x6)
3
Connector (CN198 : HMOT board)
4
Bracket (Motor) assembly
2
Two screws
(BVTT 3x6)
3-3. HOLDER ASSY
Slider assembly
Shaft
A
1
When removing, move the slider assembly
in the arrow direction, and check that shaft
A is at the position shown in the figure.
2
Connector
(CN198 :
HMOT board)
3
Remove the four screws (BVTT 3x6), and
remove the four collars (dampers) and four
compression springs.
— 27 —
3-4. BASE UNIT
3
Holder assembly
5
Base unit
(MBU-2B)
1
Leaf spring (UDL)
2
Leaf spring (UDR)
4
Three screws
(BVTP 3x6)
3-5. HMOT BOARD AND HLIM BOARD
6
7
Stopper washer
8
Gear (HEAD B)
9
Two screws
(Precision P2x3)
5
Stopper washer
Gear (HEAD C)
1
Stopper
washer
3
Lever (OWH)
2
Shaft (OWH)
4
Torsion spring (OWH)
!¡
Two screws
(PTP 2.6x6)
— 28 —
!™
HLIM board
0
HMOT board
SECTION 4
TEST MODE
4-1. Setting the Test Mode
While pressing the AMS knob, insert the power plug into the power supply inlet, and release the AMS knob.
4-2. Exiting the Test Mode
Press the REPEAT button. Unplug the power plug from an outlet.
4-3. Basic Operations of the Test Mode
All operations are performed using the AMS knob, YES button, and NO button.
The functions of these buttons are as follows.
Function
AMS knob
YES button
NO button
Changes parameters and modes
Proceeds onto the next step. Finalizes input.
Returns to previous step. Stops operations.
Contents
4-4. Selecting the Test Mode
Eight test modes are selected by turning the AMS knob.
Display
TEMP ADJUS
LDPWR ADJUS
EFBAL ADJUS
FBIAS ADJUS
FBIAS CHECK
CPLAY MODE
CREC MODE
EP MODE
Temperature compensation offset adjustment
Laser power adjustment
Traverse adjustment
Focus bias adjustment
Focus bias check
Continuous playback mode
Continuous recording mode
Non-volatile memory mode *
For detailed description of each adjustment mode, refer to 5. Electrical Adjustments.
If a different adjustment mode has been selected by mistake, press the NO button to exit from it.
* The EP MODE is not used in servicing. If set accidentally, press the NO button immediately to exit it.
4-4-1. Operating the Continuous Playback Mode
1. Entering the continuous playback mode
1 Set the disc in the unit (either MO or CD).(MO: Recordable disc, CD: Disc for playback only).
2 Rotate the AMS knob and display “CPLAY MODE”.
3 Press the YES button to change the display to “CPLAY IN”.
4 When access completes, the display changes to “C1 =
Note : The “
” displayed are arbitrary numbers.
2. Changing the parts to be played back
1 Press the YES button during continuous playback to change the display to “CPLAY MID”, “CPLAY OUT”.
When pressed another time, the parts to be played back can be changed.
2 When access completes, the display changes to “C1 =
Note : The “
” displayed are arbitrary numbers.
3. Ending the continuous playback mode
1 Press the NO button. The display will change to “CPLAY MODE”.
2 Press the §OPEN/CLOSE button and remove the disc.
Note 1 :The playback start addresses for IN, MID, and OUT are as follows.
IN 40h cluster
MID 300h cluster
OUT 700h cluster
Contents
AD = ”.
AD = ”.
— 29 —
4-4-2. Operating the Continuous Recording Mode
1. Entering the continuous recording mode
1 Set the MO disc in the unit.
2 Rotate the AMS knob and display “CREC MODE”.
3 Press the YES button to change the display to “CREC IN”.
4 When access completes, the display changes to “CREC (
Note : The “
” displayed are arbitrary numbers.
” and REC lights up.
2. Changing the parts to be recorded
1 When the YES button is pressed during continuous recording, the display changes to “CREC MID”, “CREC OUT” and REC goes
off.
When pressed another time, the parts to be recorded can be changed.
2 When access completes, the display changes to “CREC (
Note : The “
” displayed are arbitrary numbers.
” and REC lights up.
3. Ending the continuous recording mode
1 Press the NO button. The display changes to “CREC MODE” and REC goes off.
2 Press the §OPEN/CLOSE button and remove the disc.
Note 1 : The recording start addresses for IN, MID, and OUT are as follows.
IN 40h cluster
MID 300h cluster
OUT 700h cluster
Note 2 : The NO button can be used to stop recording anytime.
Note 3 : During the test mode, the erasing-protection tab will not be detected. Therefore be careful not to set the continuous recording
mode when a disc not to be erased is set in the unit.
Note 4 : Do not perform continuous recording for long periods of time above 5 minutes.
Note 5 : During continuous recording, be careful not to apply vibration.
4-4-3. Non-Volatile Memory Mode
This mode reads and writes the contents of the non-volatile memory.
It is not used in servicing. If set accidentally, press the NO button immediately to exit it.
4-5. Functions of Other buttons
Function
·
p
)
0
r
SCROLL/
CLOCK SET
PLAY MODE
DISPLAY/
CHAR
Sets continuous playback when pressed in the STOP state. When pressed during continuous playback, the tracking servo turns ON/OFF.
Stops continuous playback and continuous recording.
The sled moves to the outer circumference only when this is pressed.
The sled moves to the inner circumference only when this is pressed.
Turns recording ON/OFF when pressed during continuous playback.
Switches between the pit and groove modes when pressed.
Switches the spindle servo mode (CLVS and A).
Switches the display when pressed.Returns to previous step. Stops operations.
Note : The erasing-protection tab is not detected during the test mode. Recording will start regardless of the position of the erasing-protec-
tion tab when the r button is pressed.
Contents
— 30 —
Loading...