Kenwood KR 5600 Service Manual

The Kenwood KR 5600 is a high-performance stereo receiver featuring 60 watts per channel RMS power, quartz PLL synthesized tuning, 8 FM/8 AM station presets, loudness control, tape monitoring, and comprehensive audio controls. This service manual provides detailed technical information for service technicians, including schematics, alignment procedures, parts lists, and troubleshooting guidelines.

1. Technical Specifications 2. Block Diagram 3. Circuit Description 4. Alignment Procedures 5. Disassembly Instructions 6. Parts List 7. Schematic Diagrams 8. PCB Layouts 9. Troubleshooting Guide 10. Service Notes 11. Safety Precautions

Technical Specifications

Complete electrical and mechanical specifications for the Kenwood KR 5600 stereo receiver.

Parameter	Specification
Power Output	60W + 60W RMS (8 ohms, 20Hz-20kHz)
THD	0.03% (rated power)
Frequency Response	10Hz-50kHz (+1/-3dB)
Input Sensitivity	Phono: 2.5mV; AUX: 150mV
S/N Ratio	Phono: 76dB; AUX: 90dB
Tuning Range	FM: 87.5-108MHz; AM: 530-1620kHz
Preset Stations	8 FM, 8 AM
Dimensions	440 x 150 x 370mm (W x H x D)
Weight	11.5kg
Power Requirements	AC 120V/220V/240V, 50/60Hz

Block Diagram

System block diagram showing signal flow and major circuit sections.

Tuner Section: FM front end, IF amplifier, detector, AM tuner
Preamplifier: Phono equalizer, tone controls, selector switches
Power Amplifier: Driver stage, output transistors, protection circuit
Power Supply: Transformer, rectifiers, regulators
Control System: Microprocessor, display drivers, interface circuits

NOTE: Refer to schematic diagrams for detailed circuit connections.

Circuit Description

Detailed explanation of major circuit blocks and their operation.

Tuner Section: Quartz PLL synthesizer with varactor tuning
Phono Equalizer: RIAA equalization with low-noise transistors
Tone Control: Bass and treble controls with defeat switch
Power Amplifier: Complementary symmetry output stage
Protection Circuit: DC detection, overcurrent, and thermal protection
Power Supply: Dual voltage rails with overvoltage protection

Alignment Procedures

Step-by-step alignment instructions for proper receiver performance.

FM Alignment: Adjust front end coils L1, L2, L3 for maximum sensitivity
IF Alignment: Set ceramic filters and IF transformers to 10.7MHz
AM Alignment: Adjust oscillator and antenna trimmers for proper tracking
Stereo Decoder: Adjust separation and pilot cancellation
Power Amplifier: Set bias current and DC offset

WARNING! Use proper test equipment and follow safety procedures.

Disassembly Instructions

Procedure for disassembling the receiver for service access.

Remove top cover: Remove 6 screws from rear and sides
Remove front panel: Detach knobs and remove 4 mounting screws
Access main board: Remove shield covers and connector restraints
Tuner module: Remove mounting brackets and ribbon cables
Power supply: Discharge capacitors before servicing

CAUTION! Document cable positions and handle boards carefully.

Parts List

Complete list of components with part numbers and specifications.

Part No.	Description	Value/Type
X10-1230-01	Power Transformer	Primary: 120V, Secondary: 35V-0-35V
2SC2344	Output Transistor	NPN, 120V, 10A, 100W
2SA1011	Output Transistor	PNP, 120V, 10A, 100W
LA1260	FM IF Amplifier	IC, 10.7MHz IF system
AN7470	Stereo Decoder	IC, MPX decoder with pilot cancel
1000μF/63V	Main Filter Capacitor	Electrolytic, 85°C

Schematic Diagrams

Complete schematic diagrams for all circuit sections.

Main Amplifier Schematic: Power amp, protection, and driver stages
Tuner Section: FM/AM tuner, PLL synthesizer, and IF circuits
Preamplifier: Phono EQ, tone controls, and input selector
Power Supply: Transformer, rectifiers, and voltage regulators
Control System: Microprocessor, display, and interface circuits

Note: All schematics include component values and test points.

PCB Layouts

Printed circuit board layouts with component placement.

Main Board: Power amplifier and control circuits
Tuner Board: FM/AM tuner and PLL synthesizer
Front Panel: Display, controls, and input selectors
Power Supply Board: Rectifiers, filters, and regulators

Includes solder side and component side views with reference designators.

Troubleshooting Guide

Systematic approach to diagnosing and repairing common problems.

Symptom	Possible Cause	Corrective Action
No power	Fuse, power switch, transformer	Check F801 (4A), power switch, transformer primary
No audio output	Protection circuit, output transistors	Check protection relay, test output transistors Q701-Q704
Distorted sound	Bias current, DC offset	Adjust VR701 (bias), VR702 (offset); check driver transistors
No FM reception	Tuner power, PLL lock	Check +12V to tuner, verify PLL lock voltage at IC501 pin 9
Display issues	Microprocessor, display driver	Check IC901 power, clock crystal X901, display driver IC902

Service Notes

Important service tips and known issues with solutions.

Common failure points: Output transistors (2SC2344/2SA1011), power supply capacitors, protection relay contacts. Use original Kenwood parts for replacements. Calibration requires specific test equipment: oscilloscope, audio generator, distortion analyzer.

WARNING: High voltages present in power supply - discharge capacitors before servicing.

Safety Precautions

Essential safety procedures for service technicians.

Always disconnect AC power before servicing
Use isolation transformer when testing live circuits
Discharge large capacitors before handling
Use proper grounding techniques
Follow ESD precautions with semiconductors
Verify correct reassembly before applying power

DANGER! Lethal voltages present - qualified technicians only.