Marantz CD46 Service Manual

The Marantz CD46 is a high-quality CD player featuring advanced digital audio processing, precision laser mechanism, high-resolution DAC, optical and coaxial digital outputs, remote control operation, and comprehensive service adjustments. This service manual provides detailed technical information for qualified service technicians including schematics, alignment procedures, troubleshooting guides, and replacement parts information.

1. Technical Specifications 2. Block Diagrams 3. Circuit Descriptions 4. Disassembly Procedures 5. Alignment and Adjustment 6. Troubleshooting Guide 7. Parts List 8. PCB Layouts 9. Schematics 10. Safety Precautions 11. Service Notes

Technical Specifications

Detailed technical specifications and performance characteristics of the Marantz CD46 CD player.

Parameter	Specification
Frequency Response	20Hz - 20kHz ±0.5dB
Signal-to-Noise Ratio	>100dB
Dynamic Range	>95dB
Total Harmonic Distortion	<0.005%
Channel Separation	>90dB at 1kHz
Output Level	2.0V RMS
Digital Output	Optical and Coaxial
Power Requirements	120V AC, 60Hz, 15W
Dimensions	440mm W × 315mm D × 105mm H
Weight	5.2kg

Block Diagrams

System block diagrams showing signal flow and major components.

Main System Block Diagram: Shows overall signal path from laser pickup to audio outputs.
Digital Processing Block: Details DSP, DAC, and digital filter sections.
Power Supply Block: Illustrates AC input, rectification, and regulation stages.
Servo Control Block: Demonstrates focus, tracking, and spindle servo systems.
Control System Block: Shows microprocessor and interface circuits.

NOTE: Refer to schematics for detailed component-level information.

Circuit Descriptions

Detailed descriptions of major circuit sections and their operation.

Laser Pickup Assembly: KSS-213C mechanism with focus and tracking coils.
RF Amplifier: CXA2549M IC for RF signal processing and servo error generation.
Digital Signal Processor: CXD2545Q for EFM demodulation, error correction, and digital filtering.
DAC Section: PCM1710E 18-bit digital-to-analog converter with 8x oversampling.
Analog Output: NJM4558 op-amps for low-pass filtering and output buffering.
Power Supply: Switching regulator with ±5V and ±8V outputs.
Microprocessor: HD6433256F10 for system control and display drive.

Disassembly Procedures

Step-by-step instructions for proper disassembly and reassembly.

Remove top cover: Remove 6 Phillips screws from rear and sides.
Remove front panel: Disconnect ribbon cables and remove 4 screws.
Remove main PCB: Disconnect all connectors and remove 8 mounting screws.
Remove mechanism assembly: Disconnect flex cable and remove 4 screws.
Laser replacement: Remove shield and 2 screws holding pickup assembly.

WARNING! Always disconnect AC power before disassembly. Handle laser assembly with care to avoid electrostatic damage.

Alignment and Adjustment

Factory adjustment procedures and test points.

Required Test Equipment: Oscilloscope, audio analyzer, test CD (YEDS-18), digital voltmeter.

Adjustment	Test Point	Procedure
Laser Power	VR101	Adjust for 0.55mW at test point TP101
Focus Gain	VR102	Adjust for 2.5Vpp at TP102
Tracking Gain	VR103	Adjust for 3.0Vpp at TP103
RF Level	TP104	Verify 1.2±0.2Vpp
PLL Frequency	TP105	Adjust VC101 for 4.3218MHz

Troubleshooting Guide

Common problems and their solutions.

Symptom	Possible Cause	Corrective Action
No disc recognition	Laser failure, servo issue	Check laser power, replace pickup if <0.3mW
Disc spins but no audio	DSP or DAC failure	Check CXD2545Q and PCM1710E voltages
Intermittent playback	Power supply, mechanical wear	Check ±5V rails, inspect mechanism
No display	Microprocessor, power supply	Check +5V to μPD, reset circuit
Distorted audio	Output stage, DAC	Check NJM4558, replace PCM1710E

Service Tip: Always verify power supply voltages before replacing major ICs.

Parts List

Critical replacement parts and their specifications.

Laser Pickup: KSS-213C (Sony) or SF-92.5 (alternative)
Main Microprocessor: HD6433256F10 (Hitachi)
DSP IC: CXD2545Q (Sony)
DAC IC: PCM1710E (Burr-Brown)
RF Amplifier: CXA2549M (Sony)
Servo Processor: CXD2546Q (Sony)
Power Transistor: 2SC3852 (NEC)
Main Filter Capacitor: 4700μF/25V

PCB Layouts

Printed circuit board layouts and component locations.

Main PCB (PWB-1234-A): Component side and solder side views.
Front Panel PCB (PWB-5678-B): Display and control switches.
Power Supply PCB (PWB-9012-C): Regulator and filter components.
Mechanism Flex Cable: Connector locations and routing.

NOTE: Grounding points are critical for proper operation and noise reduction.

Schematics

Complete circuit schematics for all sections.

Main System Schematic: Shows interconnections between all major ICs and components.

Power Supply Circuit: AC input to DC outputs with protection circuits.
Digital Audio Section: DSP, DAC, and digital filter circuits.
Servo Control: Focus, tracking, and spindle motor control.
Analog Output: Low-pass filters and audio output stages.
Control System: Microprocessor, display, and key matrix.

Safety Precautions

Important safety information for service personnel.

DANGER! High voltages present in power supply section. Always disconnect AC power before servicing. Use isolation transformer when testing live circuits.

Laser Safety: Never look directly into laser lens. Laser radiation can cause eye damage.
Electrostatic Discharge: Use grounded wrist strap when handling ICs and laser assembly.
Hot Components: Power transistors and regulators may be hot during operation.
Capacitor Discharge: Large filter capacitors retain charge after power off.

Service Notes

Additional technical information and service tips.

Item	Information
Factory Service Mode	Hold STOP and PLAY while powering on
Laser Current Test	Measure voltage across R101 (10Ω) = 55mV typical
Firmware Version	Display shows VER 2.1 in service mode
Common Failures	Laser pickup (KSS-213C), power supply capacitors
Service Bulletin	SB-46-001: Improved spindle motor driver

Technical Support: Marantz Service Department 1-800-654-6633