Marantz 2200 Service Manual

The Marantz 2200 is a classic stereo receiver from the 1970s featuring 100 watts RMS per channel, dual power meters, phono inputs for turntables, tuner section with AM/FM reception, tape monitoring circuits, loudness contour, and tone controls. This service manual provides technical specifications, circuit diagrams, alignment procedures, troubleshooting guides, and parts lists for qualified service technicians. Below are key sections for specifications, block diagrams, alignment procedures, troubleshooting, and parts replacement.

1. Technical Specifications 2. Block Diagrams 3. Circuit Descriptions 4. Alignment Procedures 5. Voltage Measurements 6. Troubleshooting Guide 7. Parts List 8. Exploded Views 9. PCB Layouts 10. Safety Precautions 11. Service Notes

Technical Specifications

Key electrical and performance specifications for the Marantz 2200 stereo receiver.

Parameter	Specification
Power Output	100 watts RMS per channel (8 ohms, 20Hz-20kHz)
Total Harmonic Distortion	Less than 0.1% at rated output
Frequency Response	10Hz-50kHz (+0, -1dB)
Input Sensitivity	Phono: 2.5mV; Aux: 250mV
Signal-to-Noise Ratio	Phono: 75dB; Aux: 90dB
Damping Factor	60 at 8 ohms
Tuner Section	FM sensitivity: 1.9uV; AM sensitivity: 300uV/m
Power Requirements	120V AC, 60Hz, 450 watts max
Dimensions	19-1/4" W x 6-3/4" H x 16" D
Weight	38 lbs

Block Diagrams

System block diagrams showing signal flow and power distribution.

Main System Block Diagram: Overview of entire receiver architecture.
Preamplifier Section: Phono equalization and tone control circuits.
Power Amplifier Section: Dual mono power amplifier topology.
Tuner Section: FM/AM tuner block diagram with IF stages.
Power Supply: Dual voltage rails and regulation circuits.

WARNING! High voltages present in power supply and amplifier sections. Use isolation transformer when servicing.

Circuit Descriptions

Detailed circuit analysis of major sections.

Phono Preamp: RIAA equalization circuit using discrete transistors.
Tone Control: Bass and treble controls with center detents.
Power Amplifier: Complementary symmetry output stage with protection.
FM Tuner: FET front end with phase locked loop multiplex.
Protection Circuit: DC detection and relay delay system.

CAUTION! Always discharge power supply capacitors before working on amplifier section.

Alignment Procedures

FM Tuner Alignment: IF stages, discriminator, and oscillator adjustments.
AM Tuner Alignment: Antenna trimmer and IF transformer adjustments.
Phono Equalization: RIAA frequency response verification.
Power Amplifier Bias: Idle current adjustment procedure.
DC Offset: Output DC voltage null adjustment.
Meter Calibration: Power meter sensitivity adjustment.
Required Equipment: Audio generator, oscilloscope, VTVM, distortion analyzer.
Test Points: Locations for voltage and waveform measurements.

Voltage Measurements

Reference voltage measurements at key test points with schematic references.

Power Supply: +55V, -55V, +42V, +24V, +13V rails.

Amplifier Section: Output transistor bases, driver stages, differential inputs. Preamplifier: Phono EQ transistors, tone control IC voltages. Tuner Section: FM/AM mixer, oscillator, IF stages voltages.

Troubleshooting Guide

Common symptoms and diagnostic procedures.

No power: Check fuse, power switch, transformer primary.
One channel dead: Verify protection relay, check output transistors.
Distortion: Measure bias current, check driver transistors.
No FM reception: Verify oscillator operation, check RF amplifier.
Hum: Check ground connections, filter capacitors.

Tip: Use dim bulb tester for initial power-up after repairs.

Parts List

Complete component listing with Marantz part numbers.

Transistors: 2SC458, 2SA726, 2SC1344, output pairs.
Integrated Circuits: TA7136P phono preamp, HA1156 tone control.
Capacitors: Electrolytic, film, and ceramic types with values.
Resistors: Carbon composition and metal film values.
Potentiometers: Volume, balance, tone controls with values.
Switches: Function selector, tape monitor, loudness.
Transformers: Power, output, and choke specifications.
Meters: Power meter movement specifications.

WARNING! Use exact replacement parts for safety and performance.

Exploded Views

Mechanical assembly diagrams and disassembly sequence.

PCB Layouts

Printed circuit board artwork and component placement.

CAUTION! Note polarity and orientation when replacing components.

Safety Precautions

Always disconnect power before servicing. Use grounded tools and work surface. Beware of high voltages in power supply and amplifier sections. Replace safety critical components with exact specifications.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No power	Blown fuse, power switch	Check main fuse F801; verify power switch continuity.
One channel dead	Output transistors, protection relay	Measure output transistors; check relay RL801.
Distortion in both channels	Power supply, bias current	Check ±55V rails; adjust bias current per procedure.
No FM reception	Oscillator, RF stage	Verify FM oscillator operation; check Q101 RF amplifier.
Excessive hum	Filter capacitors, grounds	Check main filter capacitors C801/C802; verify ground connections.

Service Notes: Record original settings before adjustments. Use anti-static precautions.

Technical Support: Refer to Marantz service bulletins for updated procedures.