Sharp MD-MT821(GL) User Manual

MD-MT821/W
– 1 –
CONTENTS
Page
SAFETY PRECAUTION FOR SERVICE MANUAL (MD-MT821W ONLY)............................................................................ 2
SPECIFICATIONS ................................................................................................................................................................. 3
NAMES OF PARTS ............................................................................................................................................................... 4
OPERATION MANUAL .......................................................................................................................................................... 5
QUICK GUIDE (MD-MT821 ONLY) ....................................................................................................................................... 8
DISASSEMBLY.................................................................................................................................................................... 10
REMOVING AND REINSTALLING THE MAIN PARTS ....................................................................................................... 11
ADJUSTMENT ...................................................................................................................................................................... 12
NOTES ON SCHEMATIC DIAGRAM .................................................................................................................................. 28
BLOCK DIAGRAM ............................................................................................................................................................... 29
SCHEMATIC DIAGRAM/WIRING SIDE OF P.W.BOARD................................................................................................... 30
WAVEFORMS OF MD CIRCUIT ......................................................................................................................................... 37
TROUBLE SHOOTING ........................................................................................................................................................ 38
FUNCTION TABLE OF IC.................................................................................................................................................... 41
PARTS GUIDE/EXPLODED VIEW
PACKING OF THE SET (MD-MT821 ONLY)
SERVICE MANUAL
SHARP CORPORATION
No. S4913MDMT821/
This document has been published to be used
for after sales service only.
The contents are subject to change without notice.
• In the interests of user-safety the set should be restored to its
original condition and only parts identical to those specified be
used.
MD-MT821(GL)
MD-MT821W(BL)
MD-MT821W(GL)
Illustration: MD-MT821W
Illustration: MD-MT821

Sharp MD-MT821(GL) Specifications

General

Brand	Sharp
Model	MD-MT821(GL)
Category	MiniDisc Player
Language	English

Summary

SERVICE MANUAL SAFETY PRECAUTIONS

Laser Pickup Servicing Safety

Precautions for eye safety when handling the laser pickup assembly during service.

Eye Protection Warning

Warnings about potential eye damage from laser exposure during repairs.

TROUBLESHOOTING BASICS

Moisture Condensation Issues

Explains condensation issues and how to resolve them.

MiniDisc System Limitations

Describes normal system limitations encountered during operation.

ERROR MESSAGES AND SOLUTIONS

PLAYBACK AND RECORDING OPERATIONS

Recording Procedures

Steps for recording from CD, MD, or microphone.

DISASSEMBLY PROCEDURES

Pre-Disassembly Cautions

Important precautions before starting disassembly and repair.

ADJUSTMENT PROCEDURES

Test Mode Entry/Exit

Procedures for entering and exiting the service test mode.

Test Mode Operations Overview

Overview of various test modes for adjustment.

TEST MODE OPERATION DETAILS

AUTO1 Mode Operation

Details for AUTO1 mode operation and adjustment.

AUTO2 Mode Operation

Details for AUTO2 mode operation and adjustment.

MANUAL1 Mode Operation

MANUAL2 Mode Operation

TEST-PLAY Mode Operation

TEST-REC Mode Operation

EEPROM WRITING AND TEMPERATURE SETTING

EEPROM Writing Procedure

Steps to replace EEPROM and write initial microcomputer values.

Temperature Reference Setting

Method for setting temperature reference values.

TEST MODE CHANGE CHART

Test Mode Menu Navigation

Preautomatic Adjustment Details

Details of the pre-automatic adjustment process.

ATT ADJUSTMENT PROCEDURES

ATT Auto Adjustment

Details of automatic ATT adjustment procedures.

Pre-Manual Adjustment

Details of manual adjustment procedures.

MANUAL ATT ADJUSTMENT

PRE-ADJUSTMENT VALUE CHECK

ATT Setting Check

Details on checking ATT settings.

PLAYBACK AND RECORD MODES

Continuous Playback Operation

Playback from current position or specified address.

Continuous Record Operation

Recording from current position or specified address.

BLOCK DIAGRAM

SCHEMATIC DIAGRAM

WAVEFORMS OF MD CIRCUIT

Waveform Observation Guide

Notes on observing specific waveforms and settings.

TROUBLESHOOTING GUIDE

Unit Malfunction Troubleshooting

Troubleshooting steps when the unit does not operate.

Power On Issues

Specific troubleshooting for power issues.

DISPLAY AND AUDIO TROUBLESHOOTING

Abnormal Display Issues

Troubleshooting steps for abnormal display problems.

Playback State Errors

Troubleshooting steps when playback state is not set.

Audio Playback Circuit Faults

Troubleshooting steps for audio playback issues.

MOTOR AND RECORDING/PLAYBACK ISSUES

Spindle Motor Failure

Troubleshooting steps for spindle motor failures.

Recording/Playback Operation Failures

Troubleshooting steps for recording/playback failures.

FUNCTION TABLE OF INTEGRATED CIRCUITS

IC401 Microcomputer Functions

Function table for IC401, pins 1-57.