Marantz CD84 Service Manual

The Marantz CD84 is a high-quality CD player from the renowned audio equipment manufacturer, featuring advanced digital audio technology, precision laser mechanism, and professional-grade audio circuitry. This service manual provides comprehensive technical information for qualified service technicians, including schematics, alignment procedures, troubleshooting guides, and replacement part specifications.

Technical Specifications

Detailed technical specifications and performance characteristics of the Marantz CD84 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 Voltage	2.0V RMS
Power Requirements	220-240V AC, 50/60Hz
Power Consumption	15W
Dimensions (W x H x D)	440 x 95 x 310 mm
Weight	5.2 kg

Block Diagram Overview

System architecture and signal flow diagram of the Marantz CD84.

1. Laser Pickup Assembly: Optical system for reading CD data
2. RF Amplifier: Processes the signal from the photodiodes
3. Servo Control System: Focus, tracking, and spindle servos
4. Digital Signal Processor: EFM demodulation and error correction
5. D/A Converter: 16-bit digital to analog conversion
6. Analog Output Stage: Low-pass filtering and amplification
7. Power Supply Unit: Multiple voltage regulation
8. Control Microprocessor: System control and user interface

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

Disassembly Instructions

Step-by-step procedure for disassembling the Marantz CD84.

1. Remove top cover: Unscrew 6 Phillips screws on top panel.
2. Remove front panel: Detach 4 screws and carefully disconnect ribbon cables.
3. Access main chassis: Remove 8 chassis mounting screws.
4. Lift main PCB assembly: Support board while disconnecting all connectors.
5. Remove transport mechanism: Detach 4 transport mounting screws.

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

Circuit Descriptions

• Laser System: KSS-150A laser pickup with 3-beam tracking
• RF Amplifier: CX20109 IC for RF signal processing
• Servo Processor: CX20108 for focus and tracking control
• Digital Processor: CXD1135Q for EFM demodulation and error correction
• D/A Converter: SM5840 digital filter and PCM53JP-V D/A converter
• Analog Stage: NJM4558 op-amps for output filtering
• Power Supply: Transformer with ±12V and +5V regulated outputs
• Control System: HD4074584S microprocessor

Alignment Procedures

Detailed alignment and adjustment procedures for optimal performance.

Required Test Equipment: Oscilloscope, Audio analyzer, Test CD, DC power supply

Focus Bias Adjustment: Monitor RF envelope and adjust for maximum amplitude

Tracking Gain: Adjust for stable tracking with minimal jitter

PLL Adjustment: Set for minimum jitter on EFM signal

Output Level: Adjust for 2.0V RMS output with 0dB test signal

Troubleshooting Guide

Systematic approach to diagnosing and repairing common issues.

Symptom	Possible Cause	Corrective Action
No disc recognition	Laser failure/dirty lens	Clean lens; check laser power; replace pickup if necessary
Disc spins but no audio	RF amplifier/DSP fault	Check RF waveform; verify clock signals; test D/A converter
Intermittent playback	Servo issues/power supply	Check servo adjustments; verify power supply voltages
No display/control	Microprocessor/system reset	Check +5V supply; verify crystal oscillator; check reset circuit
Distorted audio	Analog stage fault	Check op-amp voltages; test output capacitors; verify D/A reference

Parts List

Complete list of replacement parts and components.

Part Number	Description	Qty
KSS-150A	Laser Pickup Assembly	1
CX20109	RF Amplifier IC	1
CX20108	Servo Processor IC	1
CXD1135Q	Digital Signal Processor	1
PCM53JP-V	16-bit D/A Converter	1
NJM4558	Dual Operational Amplifier	2
HD4074584S	Control Microprocessor	1

PCB Layouts

Detailed printed circuit board layouts and component locations.

1. Main PCB: Component side and solder side views
2. Power Supply PCB: Voltage regulator section
3. Display PCB: Front panel controls and indicators
4. Transport PCB: Servo driver circuits

Note: All measurements in millimeters. Component designators match schematic.

Wiring Diagrams

Complete interconnecting wiring and cable routing diagrams.

Main Harness: Power supply to main PCB connections

Front Panel: Control switches and display connections

Transport: Laser pickup and motor connections

Audio Output: RCA connector wiring

Tip: Use original cable lengths and routing to avoid interference.

Safety Precautions

Essential safety information for service personnel.

Electrical Safety: Always disconnect power before servicing. Discharge capacitors.

Laser Safety: Never look directly into laser beam. Laser class 1 product.

ESD Protection: Use grounded workstations and wrist straps.

WARNING! High voltages present in power supply. Use isolation transformer.

Service Notes

Additional technical information and service tips.

• Laser replacement requires mechanical adjustments
• Use factory test CDs for alignment procedures
• Record original adjustment positions before making changes
• Check for factory service bulletins and updates
• Verify all repairs with comprehensive testing

Service Support: Contact authorized Marantz service centers for technical assistance.