Denon DRM-800A Service Manual

Hi-Fi Component
SERVICE MANUAL
STEREO CASSETTE TAPE DECK
IVIODEL
DRM-800A
I
I TABLE OF CONTENTS I
OPERATING INSTRUCTIONS 2 - 11
SPECIFICATIONS 11
BLOCK DIAGRAM 12
LEVEL DIAGRAM 13
DISASSEMBLY INSTRUCTIONS 14 - 15
ADJUSTING AND CHECKING THE MECHANISM SECTION 15 - 17
ADJUSTING THE ELECTRICALSECTIONS 17- 19
PARTS LIST OF EXPLODED ViEW 20
EXPLODED VIEW OF CABINET AND CHASSIS GROUP _ 21
PARTS LIST OF 4U-1817/4U-1823/MECHANISM EXPLODED ViEW 22
EXPLODED VIEW OF MECHANiSM _ 23
PARTS LIST OF 4U-181 6 24
WIRING DIAGRAM/BUNDLE DIAGRAM _ 25
SCHEMATIC DIAGRAM 26-27
PW.BOARD OF 4U-1816 28
P.W.BOARD OF 4U-1817/4U-1823 29
SEMICONDUCTORS 30
NIPPON COLUMBIA CO.,LTD.

Denon DRM-800A Specifications

General

Brand	Denon
Model	DRM-800A
Category	Cassette Player
Language	English

Summary

Important Safety Information

General Safety Warnings

General warnings to prevent fire, shock hazard, and damage to the appliance.

Handling and Usage Precautions

Cautions for handling power cord, opening unit, internal objects, and environmental usage.

Electrical Safety Guidelines

Specific electrical safety for British/Australian models regarding wiring and earthing.

Recording Procedures and Settings

Basic Recording Setup and Switches

Optimal Recording Level Guidelines

Guidance on setting proper recording levels for optimal sound quality and avoiding distortion.

Noise Reduction and Monitoring Features

Monitor Button for Off-Tape Monitoring

Dolby C Noise Reduction System

Explanation of the Dolby C NR system for reducing tape background noise.

Dolby HX-PRO Headroom Extension

System for extending headroom during recording for improved treble.

Maintenance and Care Procedures

Head, Pinch Roller, and Demagnetization Cleaning

Procedures for cleaning heads, pinch rollers, capstans, and demagnetizing heads.

Troubleshooting and Technical Specifications

Common Symptoms and Resolutions

Guide to identifying and resolving common symptoms mistaken for malfunctions.

Detailed Technical Specifications

Unit Disassembly Instructions

Front Panel Removal Procedure

Mechanism Unit Removal Steps

Front Escutcheon Assembly Removal

Internal Component Disassembly

Meter Circuit Board Removal

Audio Circuit Board Removal

Power Supply Board Removal

Mechanism Adjustment and Inspection

Pinch Roller Replacement Guide

Mechanism Adjustment and Head Servicing

Pinch Roller Crimping Verification

Recording/Playback Head Replacement

Head Alignment Procedures

Steps for height, tilt angle, and azimuth adjustment of the recording/playback head.

Erasure Head Replacement

Electrical Section Adjustment Procedures

Required Tools and Test Tapes

Pre-Adjustment Preparation Notes

Tape Playback and Azimuth Alignment

Playback System Calibration

Tape Speed Verification and Adjustment

How to verify and adjust tape transport speed using a frequency counter.

Playback Level Output Adjustment

Adjusting playback level output using test tapes and specified voltage levels.

Playback Frequency Response Checks

Verifying and adjusting playback frequency characteristics using test tapes.

Recording System Calibration

Recording Frequency Response Adjustment

Adjusting recording frequency response for optimal sound reproduction.

Recording Level and Output Adjustment

Setting and verifying recording input and output levels for accurate recording.

Dolby C Recording Frequency Verification

Verifying recording/playback frequency characteristics with Dolby C NR engaged.