Sony MDSS-38 Service manual

MDS-S38

SERVICE MANUAL

Photo: Black

Model Name Using Similar Mechanism MDS-S37 MD Mechanism Type MDM-3B Optical Pick-up Type KMS-260A/J1N

SPECIFICATIONS

US Model

Canadian Model

AEP Model

UK Model

E Model

MICROFILM

MINIDISC DECK

— 1 —

CAUTION

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

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.

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.

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.

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.

ATTENTION AU COMPOSANT AYANT RAPPORT

À LA SÉCURITÉ!! LES COMPOSANTS IDENTIFIÉS P AR UNE MARQUE ! SUR LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT . NE REMPLA CER CES COMPOSANTS QUE PAR DES PIÈCES SONY DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.

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SAFETY CHECK-OUT

TABLE OF CONTENTS

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 AC voltmeter. 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

0.15µF

1.5k

Ω

AC voltmeter (0.75V)

1. SERVICING NOTE

.......................................................... 5

2. GENERAL .......................................................................... 8

3. DISASSEMBLY

3-1. Front Panel ......................................................................... 22

3-2. Back Panel and Main Board ............................................... 23

3-3. Bracket (T), (L) and (R)...................................................... 24

3-4. BD Board ........................................................................... 24

3-5. SUB Chassis........................................................................ 25

3-6. Shutter Assembly ................................................................ 25

3-7. Over Write Head ................................................................. 26

3-8. Slider Complete Assembly.................................................. 27

4. TEST MODE ..................................................................... 28

5. ELECTRICAL ADJUSTMENTS ............................... 31

6. DIAGRAMS

6-1. Circuit Boards Location ...................................................... 36

6-2. Block Diagrams

• BD Section ....................................................................... 37

• Main Section .................................................................... 39

6-3. Printed Wiring Board — BD Section — ............................. 42

6-4. Schematic Diagram — BD Section — ............................... 45

6-5. Schematic Diagram — Main Section — ............................ 49

6-6. Printed Wiring Board — Main Section —.......................... 53

6-7. Schematic Diagram — Panel Section — ............................ 55

6-8. Printed Wiring Board — Panel Section — ......................... 57

6-9. IC Block Diagrams ............................................................. 60

6-10. IC Pin Functions ............................................................... 65

Earth Ground

Fig. A. Using an AC voltmeter to check AC leakage.

MODEL IDENTIFICATION — BACK PANEL —

Parts No.

Parts No. Model

4-989-525-1 4-989-525-2 4-989-525-3 4-989-525-4 4-989-525-5 4-989-525-6 4-989-525-7

US model Canadian model AEP model UK model Singapore model Hong Kong model Tourist model

Product country

MALAYSIA MALAYSIA MALAYSIA MALAYSIA MALAYSIA MALAYSIA JAPAN

7. EXPLODED VIEWS

7-1. Main Section ....................................................................... 74

7-2. Front Panel Section ............................................................. 75

7-3. Mechanism Deck Section (1) (MDM-3B) .......................... 76

7-4. Mechanism Deck Section (2) (MDM-3B) .......................... 77

8. ELECTRICAL PARTS LIST ........................................ 78

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SECTION 1

SERVICING NOTE

JIG FOR CHECKING BD BOARD WAVEFORM

The special jig (J-2501-124-A) is useful for checking the waveform of the BD board. The names of terminals and the checking items to be performed are shown as follows.

I+3V : For measuring IOP (Check the deterioration of the optical pick-up laser) IOP : For measuring IOP (Check the deterioration of the optical pick-up laser) TEO : TRK error signal (Traverse adjustment) VC : Reference level for checking the signal RF : RF signal (Check jitter)

TEO

IOP

I + 3V

Jig

(J-2501-124-A)

CN110

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 :

Disconnect the power plug, short-circuit JW143 and JW164 on the main board with a pincette or etc.

[MAIN BOARD] (Component Side)

Mechanism deck

S301

CN302

JW143

C001

JW164

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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 data amount stored in D RAM, number of retries, and retry cause are displayed. Each is displayed in hexadecimal number.

• The display of the D RAM data amount enables data reading, accumulation, ejection, and writing to be performed smoothly. If wr iting is not smooth, data may decrease considerably.

Method:

1. Load a recordable disc whose contents can be erased into the unit.

2. Press the EDIT/NO button several times to display “All Erase?” on the fluorescent display tube.

3. Press the YES button.

4. When “All Erase??” is displayed on the fluorescent display tube, the numbers on the music calendar will start blinking.

5. Press the YES button to display “Complete”, and press the p button immediately and continue pressing for about 10 seconds.

6. When the “TOC” displayed on the fluorescent display tube goes off, release the p button.

7. Press the r button to start recording.

8. Press the DISPLAY/CHAR button to display the test mode (Fig. 1), and check the display.

9. The Rt value increases with each retry. If an error occurs after a retry, “Retry Error” will be displayed, and the number of retries counted

will be set back to 0.

10. To exit the test mode, press the POWER button. Turn OFF the power, and after “TOC” disappears, disconnect the power plug from the

outlet.

Fig. 1 Reading the Test Mode Display

SC @@ Rt # # ∗ ∗

Fluorescent Display Tube Signs

@@ : Displays the DRAM memory amount when at all times. # # : Displays the number of retries. When a retry error occurs, the number will be set back to 0. * * : Cause of retry

All three displays above are in hexadecimal numbers.

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Reading the Retry Cause Display

Higher Bits Lower Bits

Hexadecimal

Bit

Binary

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 “CLV unlock” and “ader5”.

84218421

b7 b6 b5 b4 b3 b2 b1 b0

00000000 00000001

00000010

00000100 00001000 00010000 00100000 01000000 10000000

Hexa-

decimal

00 01

04 08 10 20 40 80

Cause of Retry Occurring conditions

Spindle is slow (Not used)

ader5

Discontinuous address (Not used) FCS incorrect IVR rec error CLV unlock Access fault

When spindle rotation is detected as slow (Not used) 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 CLV is unlocked 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

0000 0001 0010 0011 0100 0101 0110 0111

9 A B C D E

1000 1001 1010 1011 1100 1101 1110 1111

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Location of Parts and Controls

SECTION 2

GENERAL

213567

18 17 1516192021

1 POWER switch 2 Remote sensor 3 Disc compartment 4 § (eject) button 5 0/) (fast backward/fast forward) buttons 6 ﬂ (play/pause) button 7 p (stop) button 8 r (recording) button 9 REC MODE switch 10 INPUT switch

11 REC LEVEL (ANALOG) knob 12 AMS knob 13 EDIT/NO/YES buttons 14 Display window 15 DISPLAY/CHAR button 16 PLAY MODE button 17 SCROLL button 18 REPEAT button 19 PHONES jack 20 PHONES LEVEL knob 21 TIMER switch

911

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