Page 1
MDS-EX77 SERVICE MANUAL AEP Model UK Model E Model MDS-EX77 is the mini disc deck section in DHC-MD77/EX77MD. U.S and foreign patents licensed from Dolby Labora- Model Name Using Similar Mechanism MDS-S37 tories Licensing Corporation. MD Mechanism Type MDM-3A Optical Pick-up Name...
COMPONENTS IDENTIFIED BY MARK ! OR DOTTED 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.
Page 3
CAUTION Danger of explosion if battery is incorrectly replaced. Replace only with the same or equivalent type recommended by the manufacturer. Discard used batteries according to the manufacturer’s instructions. ADVARSEL! Lithiumbatteri-Eksplosionsfare ved fejlagtig håndtering. Udskiftning må kun ske med batteri af samme fabrikat og type.
SECTION 1 SERVICING NOTES 1-1. POWER SUPPLY DURING SERVICING 1-2. FLUORESCENT INDICATOR TUBE/BUTTONS/ JOG&LEDs CHECK MODE This set has no power supply in it, and it does not operate indi- vidually. Therefore, connect to the pre/main amplifier system (TA- 1. While pressing the CD SYNC + CONTINUE buttons simul- EX77) for the DHC-MD77 or DHC-EX77MD in servicing.
1-4. RETRY CAUSE DISPLAY MODE AT RECORD Outline: • In this mode, a cause of retry at recording can be displayed. Thus, it will help find out a faulty location of the set. • The contents displayed are data quantity stored in D-RAM, re- try count, and retry cause.
Page 6
Table 1-1. Description of Retry Cause Display Lower Bit Upper Bit Hexa- Name of Hexa- decimal Description Retry Cause decimal spindle slow When spindle speed slow was detected shock *1 When shock over 3.5 was detected When ADER was counted more than 5 times ader 5 successively Decimal...
SECTION 3 DISASSEMBLY • This set can be disassembled in the order shown below. CASE, FRONT PANEL SECTION (Page 19) MECHANISM DECK (Page 20) BD BOARD SLIDER COMPLETE BRACKET (T), (L), (R) SUB CHASSIS OVER WRITE HEAD (Page 21) ASS'Y (Page 21) (Page 20) (Page 22)
Page 21
BD BOARD 2 flat cable (15 core) (CN106) 4 OP relay flexible board (CN101) 1 flexible board (over write head) 5 BD board 3 screws (BVTT2 × 4) SUB CHASSIS 1 two step screws 1 two step screws 2 two insulators 2 two insulators part A part A...
Page 22
SHUTTER ASS’Y 1 stopper washer 2 shaft (shutter) A shutter ass’y shaft (shutter) B 3 shutter ass’y shaft (shutter) A hole B hole A When installing, install the shaft (shutter) A into the hole as show in the figune before installing the shaft (shutter) B into the hole B.
Page 23
SLIDER COMPLETE ASS’Y claw 3 Set the shaft of gear (LB) to be at the position in the figure. claw 45° 1 special screw 2 retainer (gear) 4 Remove the slider complete ass’y (M1.7 × 1.4) in the direction of arrow with putting out of two claws.
SECTION 4 TEST MODE 4-1. PRECAUTIONS FOR USE OF TEST MODE 4-5. SELECTING THE TEST MODE 1. As loading related operations will be performed regardless of Thirteen test modes are selected by turning the SELECTOR knob. the test mode operations being performed, be sure to check that the disc is stopped before setting and removing it.
4-6. OPERATING THE CONTINUOUS PLAYBACK 4-7. OPERATING THE CONTINUOUS RECORDING MODE MODE 4-6-1. Entering the Continuous Playback Mode 4-7-1. Entering the Continuous Recording Mode 1. Set the disc in the unit. (Whichever recordable discs or discs 1. Set the MO disc in the unit. (Refer to note 3.) for playback only are available.) 2.
4-8. EEP MODE 1. MODE display Displays “TEMP ADJUST”, “CPLAY MODE”, etc.. This mode reads and writes the contents of the non-volatile memory. 2. Error rate display It is not used in servicing. If set accidentally, press the Error rates are displayed as follows. EDIT/NO button immediately to exit it.
SECTION 5 ELECTRICAL ADJUSTMENTS 5-3. PRECAUTIONS FOR ADJUSTMENTS 5-1. PRECAUTIONS FOR CHECKING LASER DI- 1) When replacing the following parts, perform the adjustments ODE EMISSION and checks with ® in the order shown in the following table. To check the emission of the laser diode during adjustments, never view directly from the top as this may lose your eyesight.
Page 28
5-5. TEMPERATURE COMPENSATION OFFSET 5-6. LASER POWER ADJUSTMENT ADJUSTMENT Connection: Save the temperature data at that time in the non-volatile memory laser power meter as 25 °C reference data. Notes: 1. Usually, do not perform this adjustment. 2. Perform this adjustment in an ambient temperature of 22 °C to Optical pick-up 28 °C.
5-7. TRAVERSE (E-F BALANCE) ADJUSTMENT 8. Turning the SELECTOR knob so that the waveforms of the oscilloscope becomes the specified value. (When the Note 1: Data will be erased during MO reading if a recorded SELECTOR knob is turned, the “ ” of “EFB= MO-W”...
5-8. FOCUS BIAS ADJUSTMENT 5-9. ERROR RATE CHECK Adjusting Method: 5-9-1. CD Error Rate Check 1. Load a continuously recorded disc (Refer to “5-4. Creating Checking Method: MO Continuously Recorded Disc”.). 1. Load a test disc TDYS-1. 2. Turning the SELECTOR knob and display “CPLAY MODE”. 2.
MDS-EX77 6-1. BLOCK DIAGRAM (1/2) ADDT DADT HR901 OVER WRITE HEAD MD DIGITAL OPTICAL OVER WRITE OVER WRITE OPTICAL EFMO ADDT INPUT HEAD DRIVE HEAD DRIVE DIGITAL IN IC301 Q181, 182 IC181 DIGITAL INPUT WAVE SHAPER CD PLAYER SELECTOR Q180...
6-7. IC PIN FUNCTION DESCRIPTION BD BOARD IC101 CXA2523R (RF AMPLIFIER) Pin No. Pin Name I / O Function I-V converted RF signal I input from the optical pick-up block detector I-V converted RF signal J input from the optical pick-up block detector Middle point voltage (+1.65V) generation output terminal 4 to 9 A to F...
Page 55
BD BOARD IC121 CXD2650R (DIGITAL SIGNAL PROCESSOR, DIGITAL SERVO PROCESSOR, EFM/ACIRC ENCODER/DECODER, SHOCK PROOF MEMORY CONTROLLER, ATRAC ENCODER/DECODER, 2M BIT D-RAM) Pin No. Pin Name I / O Function Focus OK signal output to the system controller (IC401) “H” is output when focus is on SHCK Track jump detection signal output to the system controller (IC401) XBUSY...
Page 56
Pin No. Pin Name I / O Function DVSS — Ground terminal (digital system) Output enable signal output to the external D-RAM Not used (open) XCAS Column address strobe signal output to the external D-RAM Not used (open) Address signal output to the external D-RAM Not used (open) XRAS Row address strobe signal output to the external D-RAM...
Page 57
Pin No. Pin Name I / O Function TRDR Tracking servo drive PWM signal (–) output to the BH6511FS (IC152) TFDR Tracking servo drive PWM signal (+) output to the BH6511FS (IC152) DVDD — Power supply terminal (+3.3V) (digital system) FFDR Focus servo drive PWM signal (+) output to the BH6511FS (IC152) FRDR...
Page 58
MAIN BOARD IC201 CXD8607N (A/D, D/A CONVERTER) Pin No. Pin Name I / O Function INRP R-ch analog signal (+) input terminal INRM R-ch analog signal (–) input terminal REFI Reference voltage (+3.3V) input terminal (for A/D converter section) AVDD —...
Page 59
Pin No. Pin Name I / O Function VDD2 — Power supply terminal (+5V) (for L-ch side D/A converter section, digital system) VDD1 — Power supply terminal (+5V) (for A/D converter section, digital system) VDD1 — Power supply terminal (+5V) (for A/D converter section, digital system) VSS1 —...
Page 60
MAIN BOARD IC401 RU8X12MF-0010 (SYSTEM CONTROLLER) Pin No. Pin Name I / O Function DAOUT0 Output terminal for the test C1 is output when test mode DAOUT1 Output terminal for the test ADER is output when test mode Key input terminal (A/D input) KEY0 fl, ), 0, p, ENTER/YES, EDIT/NO keys input (S701 to S706) Key input terminal (A/D input)
Page 61
Pin No. Pin Name I / O Function LD LOW Loading motor voltage control signal output to the loading motor driver (IC311) — Not used (open) MNT2 Monitor 2 signal input from the CXD2650R (IC121) MNT3 Monitor 3 signal input from the CXD2650R (IC121) LED0 LED drive signal output terminal Not used (open)
Page 62
Pin No. Pin Name I / O Function BEEP Beep sound drive signal output terminal Not used (open) ADARES Reset signal output to the A/D, D/A converter (IC201) “L”: reset SWL-A Not used (open) SEL-B Not used (open) Laser modulation select signal output Playback power: “L”, Stop: “H”, Recording power: 0.5 sec...
Remark Ref. No. Part No. Description Remark X-4947-652-1 PANEL ASSY, FRONT 3-363-099-01 SCREW (CASE 3 TP2) 4-962-708-01 EMBLEM (4-A), SONY * 15 4-985-899-11 CASE 4-985-889-01 BUTTON (REC) (CD SYNC, r REC) * 16 4-985-898-12 PANEL (MDS), BACK 4-985-890-01 BUTTON (MODE)
Page 64
(2) MECHANISM DECK SECTION-1 (MDM-3A) not supplied not supplied supplied not supplied not supplied Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark 4-628-167-01 SCREW, STEP 1-660-966-11 OP RELAY FLEXIBLE BOARD 4-987-327-01 INSULATOR * 57 A-4699-092-A BD BOARD, COMPLETE 4-986-959-01 WASHER, STOPPER 1-777-517-11 WIRE (FLAT TYPE) (15 CORE) 4-987-736-01 SHAFT (SHUTTER)
Page 65
(3) MECHANISM DECK SECTION-2 (MDM-3A) not supplied not supplied not supplied M902 M903 M901 HR901 The components identified by mark ! or dotted line with mark ! are critical for safety. Replace only with part number specified. Ref. No. Part No. Description Remark Ref.
SECTION 8 ELECTRICAL PARTS LIST NOTE: • Due to standardization, replacements in the • Items marked “*” are not stocked since they The components identified by mark parts list may be different from the parts speci- are seldom required for routine service. ! or dotted line with mark ! are critical for safety.
Page 67
MAIN Ref. No. Part No. Description Remark Ref. No. Part No. Description Remark IC171 8-759-428-58 IC XL24C01AF-E2 R142 1-216-073-00 METAL CHIP 1/10W IC181 8-759-095-65 IC TC74ACT540FS R143 1-216-073-00 METAL CHIP 1/10W IC192 8-759-426-95 IC L88MS33T-TL R144 1-216-025-00 METAL CHIP 1/10W <...