Denon DRA-375RD Service Manual

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Hi-Fi
AM-FM
Stereo
Receiver
SERVICE MANUAL
MODEL DRA-3 75RD
MODEL DRA-275RD/275R
AM-FM STEREO RECEIVER
DRA-275R
— TABLE OF CONTENTS —
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@ Some illustration using in this service manual is slightly different from the actual set.
NIPPON
COLUMBIA
CO.
LTD.

Denon DRA-375RD Specifications

General

Total Harmonic Distortion (THD)	0.08%
Input Sensitivity	2.5mV (MM), 150mV (line)
Tuning range	FM, MW
Frequency Response	20 Hz - 20 kHz
Signal-to-Noise Ratio	100 dB
Output	Speakers A/B, Headphones
Speaker load impedance	8Ω to 16Ω
Inputs	Phono, CD, Tape, Aux
Outputs	Tape out, headphones

Summary

Safety Precautions

General Safety Warnings

Essential safety warnings for electrical shock, fire, and moisture to prevent hazards.

Usage and Installation Precautions

Installation Precautions

Front Panel Controls and Indicators

Front Panel Controls

Detailed description of buttons, knobs, and jacks on the receiver's front panel.

Rear Panel Connections

Rear Panel Layout and Connectivity

Identification and description of input/output terminals on the rear panel for various connections.

Tuner Functions and Operations

Tuner Controls and Features

Explanation of buttons and controls related to the tuner section, including RDS and memory functions.

Remote Control Operation

Remote Control Setup and Usage

Instructions for inserting batteries, operating the remote control unit, and general usage notes.

Troubleshooting Guide

Common Issues and Solutions

A guide to diagnose and resolve common problems encountered with the receiver's operation.

Technical Specifications

Amplifier and Video Specifications

Detailed electrical and performance specifications for the amplifier and video sections.

Tuner and General Specifications

Technical details for the tuner section, dimensions, weight, and remote control unit.

Disassembly Procedures

Unit Disassembly Steps

Adjustment Procedures

Idling Current Adjustment

Instructions for setting the idling current for the amplifier section using a DC voltmeter.

Measurement and Memory Operations

FM Section Measurement Setup

Memory Clearing Procedure

Block and Level Diagrams

Receiver Block Diagram

A high-level overview of the receiver's internal circuitry and signal flow.

Semiconductor Component Details

IC Port Allocation

Printed Wiring Board Diagrams

Main Unit PCB Layout

Printed Wiring Board Diagrams (Continued)

Display Unit PCB Layout

Parts Listings

Main Unit Component List

Parts Listings (Continued)

Resistor and Capacitor Lists

Tuner Unit Component Lists

Display Unit Component Lists

Exploded View Diagrams

Chassis and Cabinet Assembly

Parts Lists (Continued)

Exploded View Parts Identification

Wiring Diagrams

Overall Wiring Diagram

Schematic Diagrams

Schematic Diagram Part 1

The first part of the detailed circuit schematic for the receiver.

Schematic Diagrams (Continued)

Schematic Diagram Part 2

The second part of the detailed circuit schematic for the receiver.