Marantz PM 35 Service Manual

The Marantz PM 35 is a high-quality stereo integrated amplifier featuring advanced audio circuitry, multiple input options, and robust construction. This service manual provides comprehensive technical information for qualified service personnel, including schematics, alignment procedures, parts lists, and troubleshooting guidelines for proper maintenance and repair of the amplifier.

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

Technical Specifications

Complete electrical and mechanical specifications for the Marantz PM 35 integrated amplifier.

ParameterSpecification
Power Outputxx Watts per channel (xx Ohms)
Total Harmonic Distortion<0.xx% (xx Hz - xx kHz)
Frequency Responsexx Hz - xx kHz (+0/-x dB)
Input Sensitivityxx mV (PHONO), xx mV (LINE)
Signal-to-Noise Ratio>xx dB (PHONO), >xx dB (LINE)
Input Impedancexx kOhms (PHONO), xx kOhms (LINE)
Damping Factor>xx (xx Ohms)
Power Consumptionxx Watts (max)
Dimensions (W x H x D)xxx x xx x xx mm
Weightxx kg

Block Diagram and Circuit Description

Detailed explanation of the amplifier's functional blocks and circuit operation.

  1. Power Supply Section: Transformer, rectification, and regulation circuits
  2. Preamplifier Stage: Phono equalization and line amplification
  3. Tone Control Circuit: Bass, treble, and balance controls
  4. Power Amplifier Section: Driver and output stages
  5. Protection Circuitry: DC protection and thermal management

WARNING! High voltages present in power supply section. Exercise extreme caution when servicing.

Disassembly Instructions

Step-by-step procedure for accessing internal components.

  1. Remove top cover: Unscrew x screws located on top panel
  2. Remove bottom cover: Unscrew x screws from bottom
  3. Front panel removal: Detach knobs and remove x front panel screws
  4. PCB access: Remove mounting screws and carefully lift circuit boards
  5. Heat sink removal: Note thermal compound application for reassembly

CAUTION! Handle circuit boards by edges to prevent electrostatic damage.

Adjustment and Alignment Procedures

Schematic Diagrams

Complete circuit schematics for all sections of the amplifier.

Main Schematic: Power amplifier, preamplifier, and power supply circuits

Sub-schematics: Tone control, input selector, protection circuits

All component values and reference designators clearly marked. Signal flow indicated with arrows. Test points and adjustment points clearly identified.

Parts List and Exploded Views

Comprehensive listing of all components with manufacturer part numbers.

ReferenceDescriptionPart NumberQty
R101Resistor xx Ohm xx WattMAR-xxxxx1
C205Capacitor xx uF xx VMAR-xxxxx1
Q301Transistor NPN2SCxxxx2
IC401Integrated CircuitNJMxxxx1
F101Fuse xxAMAR-xxxxx1

Exploded mechanical views showing assembly sequence and hardware locations.

PCB Layouts

Detailed printed circuit board layouts for all boards.

  1. Main amplifier board: Component and solder side views
  2. Power supply board: Component placement and routing
  3. Front panel board: Switch and control layouts
  4. All boards include silkscreen identification and test points

Tip: Use exact replacement components to maintain performance specifications.

Troubleshooting Guide

Systematic approach to diagnosing and repairing common issues.

SymptomPossible CauseCorrective Action
No powerFuse, power switch, transformerCheck F101, measure primary voltage, test power switch
Distorted outputBias current, output transistorsAdjust bias current, test output devices, check driver stage
Hum/buzzGrounding, filter capacitorsCheck ground connections, test main filter capacitors
One channel deadProtection circuit, amplifier stageCheck protection relay, measure DC offset, test signal path
Intermittent operationCold solder joints, connectorsInspect solder joints, clean and reseat connectors

Safety Precautions

Essential safety information for service personnel.

WARNING! Line voltages present even when unit is switched off. Always disconnect from mains before servicing. Large filter capacitors retain dangerous charge - discharge before handling.

Use isolation transformer when testing live circuits. Follow ESD precautions when handling semiconductors.

Service Notes

Important service information and common repair procedures.

Factory service bulletins and updates. Common failure modes and recommended replacement parts. Alignment procedures requiring special test equipment. Warranty service procedures and documentation requirements.

Service Contact: Authorized Marantz service centers only. Use genuine Marantz replacement parts.

Marantz PM 35 Service Manual © - All Rights Reserved 2025