Marantz CD 46 Service Manual

The Marantz CD 46 is a high-quality CD player featuring advanced digital audio technology, precision laser mechanism, high-resolution digital-to-analog conversion, remote control operation, multiple audio outputs, 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 Diagram Overview 3. Disassembly Instructions 4. Circuit Descriptions 5. Alignment Procedures 6. Troubleshooting Guide 7. Parts List 8. Schematic Diagrams 9. PCB Layouts 10. Service Notes 11. Safety Precautions

Technical Specifications

Complete technical specifications and performance characteristics of the Marantz CD 46 CD player.

Parameter	Specification
Audio Channels	2 (Stereo)
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	Coaxial, Optical
Power Requirements	120V AC, 60Hz / 230V AC, 50Hz
Power Consumption	15W
Dimensions (W×H×D)	440×95×315 mm
Weight	4.5 kg

Block Diagram Overview

System block diagram showing signal flow and major functional blocks.

Laser Pickup Assembly: Reads digital data from CD surface
RF Amplifier: Processes raw signal from laser pickup
Servo Control System: Focus, tracking, and spindle servos
Digital Signal Processor: EFM demodulation, error correction
Digital Filter: Oversampling digital filter
D/A Converter: 1-bit or multi-bit conversion system
Analog Output Stage: Low-pass filtering and amplification
Power Supply: Regulated DC voltages for all sections
Microcontroller: System control and user interface
Display Driver: Front panel display control

WARNING! Only qualified technicians should attempt service procedures. High voltages present.

Disassembly Instructions

Step-by-step disassembly procedure for accessing internal components.

Power off and unplug the unit from AC mains
Remove the top cover by unscrewing 6 Phillips screws
Remove the front panel assembly: 4 screws at top and bottom
Detach the display ribbon cable carefully
Remove the main PCB: 8 mounting screws and connectors
Access the transport mechanism: Remove 4 mounting screws
Laser pickup assembly: Remove E-ring and slide rail

CAUTION! Handle laser assembly with care. Avoid static discharge.

Circuit Descriptions

Power Supply Circuit: Switching regulator with multiple DC outputs (+5V, +12V, -12V)
Laser Drive Circuit: Laser power control and APC (Automatic Power Control)
RF Amplifier: I/V conversion and RF signal processing
Servo Circuits: Focus, tracking, sled, and spindle motor control
Digital Signal Processing: EFM demodulation, CIRC error correction
Digital Filter: 8-times oversampling with noise shaping
D/A Converter: High-quality digital-to-analog conversion
Analog Output: Dual op-amp low-pass filter and buffer
Microcontroller System: System control, display, and key matrix

Alignment Procedures

Factory alignment procedures and test points for optimal performance.

Required Test Equipment: Oscilloscope, Audio analyzer, Test CD, Digital voltmeter

Laser Power Adjustment: Monitor test point TP1, adjust VR101 for 0.5V
Focus Gain Adjustment: Using test CD, adjust for minimum jitter
Tracking Gain Adjustment: Optimize for stable tracking
RF Level Adjustment: Adjust for 1.2Vp-p at RF test point
PLL Adjustment: Set for minimum data error rate
Output Level Calibration: Adjust for 2.0V RMS at 1kHz

Troubleshooting Guide

Common symptoms and diagnostic procedures.

Symptom	Possible Cause	Corrective Action
No power	Power supply fault, fuse	Check AC input, fuse F101, power supply IC
No disc recognition	Laser assembly, spindle motor	Check laser emission, focus search, spindle rotation
Skip or mistracking	Dirty lens, servo issues	Clean lens, check tracking servo, replace pickup
No audio output	DAC, analog stage	Check digital signal, DAC IC, output op-amps
Display issues	Display driver, microcontroller	Check voltages, ribbon cable, driver IC
Remote control not working	Remote sensor, power	Check sensor voltage, remote battery, microcontroller

Parts List

Complete list of replacement parts with manufacturer part numbers.

Part Number	Description	Qty
CDM-12.1	Laser Pickup Assembly	1
KSS-213C	Alternative Laser Pickup	1
LA6531	Servo Driver IC	1
CXD2565Q	Digital Signal Processor	1
PCM1710	D/A Converter IC	1
NJM4560	Dual Op-amp	2
F101	1A Fuse	1
TR101-104	Power Transistors	4

Schematic Diagrams

Complete schematic diagrams for all circuit sections.

Main Power Supply Schematic
Laser and RF Amplifier Schematic
Servo Control Schematic
Digital Processing Schematic
Audio Output Stage Schematic
Microcontroller and Display Schematic
Remote Control Receiver Schematic

Note: Schematics show component values, test points, and voltage readings.

PCB Layouts

Printed circuit board layouts and component placement diagrams.

Main PCB Top Side: Component placement and routing
Main PCB Bottom Side: Solder side and ground planes
Power Supply PCB: High-voltage section layout
Front Panel PCB: Display and controls layout
Transport Mechanism: Mechanical assembly diagram

CAUTION! Observe electrostatic discharge precautions when handling PCBs.

Service Notes

Important service tips and common repair procedures.

Laser Pickup Replacement: Always check laser current after replacement. Adjust if necessary.

Transport Mechanism: Lubricate sliding parts with specified grease only.

Software Issues: Check microcontroller reset circuit and clock crystal.

Intermittent Problems: Check for cold solder joints, especially on large components.

Factory Updates: Refer to latest service bulletins for design changes.

Safety Precautions

Essential safety information for service technicians.

Hazard	Precaution
Electric Shock	Disconnect from mains before servicing. Discharge large capacitors.
Laser Radiation	Never look directly into laser lens. Laser class 1 product.
Static Discharge	Use grounded wrist strap when handling ICs.
Hot Surfaces	Allow time for cooling after operation.
Chemical Hazards	Use proper ventilation when cleaning with solvents.

Service Support: For technical assistance, contact Marantz service department.