Marantz 5220 Service Manual

The Marantz 5220 is a professional-grade stereo cassette deck featuring 3-head design, Dolby B/C noise reduction, bias fine adjustment, peak level meters, direct drive motor, and comprehensive recording/playback controls. This service manual provides detailed technical information for qualified service technicians, including schematics, alignment procedures, troubleshooting guides, and replacement parts lists.

1. Technical Specifications 2. Block Diagrams 3. Circuit Descriptions 4. Mechanical Adjustments 5. Electrical Adjustments 6. Test Procedures 7. Troubleshooting Guide 8. Parts List 9. Exploded Views 10. PCB Layouts 11. Safety Precautions

Technical Specifications

Complete technical specifications and performance characteristics of the Marantz 5220 cassette deck.

ParameterSpecification
Frequency Response20Hz - 20kHz (±3dB)
Signal-to-Noise Ratio72dB (Dolby C)
Wow & Flutter0.025% WRMS
Input SensitivityLine: 50mV, Mic: 0.25mV
Output LevelLine: 0.5V, Headphone: 30mW
Power Requirements120V AC, 60Hz, 25W
Dimensions440 x 130 x 310mm (WxHxD)
Weight7.5kg
Heads3-head system (erase, record, playback)
MotorDC servo direct drive

Block Diagrams

System block diagrams showing signal flow and control circuits.

  1. Main System Block Diagram: Overall signal path from input to output.
  2. Record/Playback Circuit Block Diagram: Detailed recording and playback signal flow.
  3. Motor Control Block Diagram: DC servo motor control system.
  4. Power Supply Block Diagram: Voltage regulation and distribution.
  5. Dolby Noise Reduction Block Diagram: Dolby B/C processing circuits.

WARNING! Service should only be performed by qualified technicians familiar with audio equipment repair.

Circuit Descriptions

Detailed descriptions of major circuit sections and their operation.

  1. Record Amplifier Circuit: Explanation of recording signal processing.
  2. Playback Amplifier Circuit: Playback equalization and amplification.
  3. Bias Oscillator Circuit: High-frequency bias generation.
  4. Motor Drive Circuit: DC servo motor control and speed regulation.
  5. Dolby IC Circuits: Dolby B/C noise reduction implementation.
  6. Power Supply Circuit: Voltage generation and regulation.

CAUTION! Always disconnect power before servicing and discharge large capacitors.

Mechanical Adjustments

Electrical Adjustments

Required test equipment: Audio generator, oscilloscope, distortion analyzer, test tapes.

Playback Adjustments: Playback level, frequency response, channel balance.

Record Adjustments: Record level, bias current, erase current, Dolby level.

Motor Speed: Adjust reference oscillator for correct tape speed (1-7/8 ips).

Meter Calibration: Peak level meter adjustment for accurate level indication.

Test Procedures

Step-by-step testing procedures for performance verification.

  1. Power Supply Tests: Verify all DC voltage levels under load.
  2. Playback Tests: Frequency response, distortion, channel separation.
  3. Record Tests: Record/playback frequency response and distortion.
  4. Dolby Tests: Dolby tracking and noise reduction effectiveness.
  5. Mechanical Tests: Wow & flutter, tape speed accuracy.
  6. Function Tests: All mode switches and control operations.

Tip: Use manufacturer-approved test tapes for accurate measurements.

Troubleshooting Guide

Common problems and their solutions for the Marantz 5220.

SymptomPossible CauseCorrective Action
No powerFuse, power switch, transformerCheck fuse F801; test power switch; verify transformer output.
No playbackHead connections, playback ampCheck playback head wiring; test IC301/302; verify switches.
Poor recordingBias oscillator, record ampTest Q601/Q602; check record level adjustment; verify bias current.
Motor not runningMotor drive circuit, beltsCheck IC501; test motor voltage; inspect drive belts.
Speed variationMotor control, capstanAdjust VR502; clean capstan shaft; check FG head.
Dolby not workingDolby IC, level settingsTest IC401/402; verify Dolby level calibration.

Parts List

Complete listing of all components with manufacturer part numbers.

  1. Semiconductors: Transistors, diodes, ICs with original part numbers.
  2. Capacitors: Electrolytic, ceramic, film capacitors with values and ratings.
  3. Resistors: Carbon film and metal film resistors with tolerances.
  4. Mechanical Parts: Belts, idlers, gears, springs with dimensions.
  5. Heads: Record, playback, and erase head part numbers.
  6. Hardware: Screws, nuts, washers, and fasteners.

WARNING! Use only manufacturer-specified replacement parts.

Exploded Views

Detailed mechanical exploded views with part number references.

PCB Layouts

Printed circuit board layouts showing component placement and traces.

CAUTION! Observe proper ESD precautions when handling PCBs.

Safety Precautions

Important safety information for service technicians.

PrecautionDescription
Electrical SafetyAlways disconnect power before servicing; discharge large capacitors.
ESD ProtectionUse grounded wrist strap when handling semiconductors.
Test EquipmentEnsure proper grounding of all test equipment.
Component ReplacementReplace with identical specifications; observe polarity.
High VoltageBe aware of high voltage points in power supply.

Reset: Complete realignment required after major component replacement.

Service Note: This manual is intended for qualified service personnel only.

Marantz 5220 Service Manual © - All Rights Reserved 2025