Marantz PMD 222 Service Manual

The Marantz PMD 222 is a professional portable cassette recorder featuring three-head configuration, Dolby B/C noise reduction, pitch control, line/mic inputs with level controls, built-in condenser microphone, VU meters, auto/manual record level, cue/review functions, and operates on AC power or batteries. Below are key sections for technical specifications, circuit descriptions, alignment procedures, troubleshooting, and parts list.

1. Technical Specifications 2. Block Diagram & Circuit Description 3. Disassembly Instructions 4. Mechanical Adjustments 5. Electrical Adjustments 6. Head Alignment 7. Troubleshooting Guide 8. Schematic Diagrams 9. Parts List 10. Exploded Views 11. Service Notes

Technical Specifications

Key technical parameters and performance characteristics of the Marantz PMD 222.

Parameter	Specification
Heads	3-head configuration (erase, record, playback)
Noise Reduction	Dolby B and C
Frequency Response	30Hz - 16kHz (±3dB)
Wow & Flutter	0.08% (WRMS)
Signal-to-Noise Ratio	68dB (with Dolby C)
Inputs	Line, Mic, Remote
Outputs	Line, Headphone
Power Requirements	AC 120V/230V, DC 9V batteries
Dimensions	268 x 95 x 215 mm
Weight	2.8 kg (with batteries)

Block Diagram & Circuit Description

Detailed explanation of the electronic circuits and signal flow.

Record/Playback Amplifier Circuit: IC201 and associated components
Dolby Noise Reduction Circuit: IC301 for B/C processing
Motor Control Circuit: Speed regulation and torque control
Power Supply Circuit: Voltage regulation and distribution
Microphone Preamp: Built-in condenser mic amplification

WARNING! High voltages present in power supply section. Disconnect power before servicing.

Disassembly Instructions

Step-by-step procedure for accessing internal components.

Remove battery cover and batteries
Remove 6 screws from bottom case
Separate top and bottom cases carefully
Remove front panel assembly (4 screws)
Access main PCB by removing shield

CAUTION! Handle ribbon cables carefully to avoid damage.

Mechanical Adjustments

Belt Replacement: Use FRM9.5 belt, clean pulley surfaces
Motor Torque: Adjust VR601 for proper tape tension
Fast Forward/Rewind: Check clutch mechanism and springs
Head Height: Adjust head mounting screws for proper tape contact
Pinch Roller Pressure: Verify 400-500g pressure

Electrical Adjustments

Required test equipment: oscilloscope, audio generator, VTVM, test tape.

Adjustment Points: PB Level (VR202), Rec Level (VR102), Bias (VR101), Dolby Level (VR302).

Playback Frequency Response: Use 333Hz/10kHz test tape, adjust for flat response. Record Level: Set for 0dB on VU meters with 1kHz reference. Bias Current: Adjust for maximum output at 10kHz.

Head Alignment

Proper alignment procedure for record and playback heads.

Azimuth: Use 6.3kHz or 10kHz test tape, adjust for maximum output
Height: Ensure tape contacts entire head surface
Tangency: Verify proper tape wrap around head
Azimuth Screw: Located on head mounting plate

Tip: Use mirror alignment tape for visual verification.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
No power	Power supply, fuse, switch	Check F101 (1A), Q101-Q104, power switch
No playback	Head, amplifier circuit	Check head connections, IC201, test points
Poor recording	Bias, record head	Adjust VR101, check record head wear
Speed variation	Motor, belt, capstan	Check motor voltage, belt condition, capstan bearing
Dolby not working	IC301, switches	Verify IC301 operation, Dolby switch contacts

Reset: Check all adjustments after component replacement.

Schematic Diagrams

Complete circuit schematics including:

Main amplifier board (PCB-A)
Power supply section
Motor control circuit
Dolby processing board
Front panel controls

Note: All voltages measured with respect to ground.

Parts List

Critical replacement components and part numbers.

Component	Part Number	Description
Playback Head	522-022-30011	Ferrite head assembly
Record Head	522-022-30012	Ferrite head assembly
Capstan Motor	522-500-2001	FG servo motor
Main Belt	522-900-1005	FRM9.5 timing belt
IC201	LA3166	Dual preamplifier
IC301	CX20188	Dolby B/C processor

Exploded Views

Mechanical assembly diagrams showing component relationships.

Main chassis assembly
Head mechanism detail
Front panel assembly
Drive mechanism
PCB mounting

CAUTION! Note spring locations and orientation during reassembly.

Service Notes

Important service tips and common issues.

Common Failures: Belt deterioration, head wear, Dolby switch oxidation, capacitor leakage in power supply. Special Tools: Azimuth alignment tool, belt installation tool, demagnetizer. Calibration: Requires MTT-150 test tape for proper alignment.