Korg POLY-61 Service Manual

PROGRAMMABLE
POLYPHONIC SYNTHESIZER
SERVICE MANUAL
POIY-61
CONTENTS
1. SPECI U ‘’CATIONS. 1
2. STRUCTURAL DIAGRAM. 2
3. BLOCK DIAGRAM. 4
4. CIRCUIT DIAGRAM. 5
5. REFERENCE DATA. 9
6. PC BOARD . 10
7. SETTING CHAS iS. 18
8. CHECK AND ADJUSTMENT PROCEDURE .... 19
9. PARTS LIST . 25
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KEIO ELt-CTHONIC LABORATORY CORPORATION
TOKYO/JAPAN

Korg POLY-61 Specifications

General

Type	Analog
Polyphony	6 voices
LFO	1 LFO
Keyboard	61 keys
Memory	64 patches
Year released	1982
Oscillators	2 per voice
Waveforms	Saw, Pulse
Control	MIDI

Summary

1. SPECIFICATIONS

Keyboard and Module Parameters

Panel Controls and Outputs

3. BLOCK DIAGRAM

System Block Diagram

High-level block diagram illustrating the Poly-61's internal architecture.

4. CIRCUIT DIAGRAM

KLM-475 and KLM-509 Circuit Diagrams

KLM-476 Circuit Diagram

KLM-477 Circuit Diagram

KLM-478 and KLM-479 Circuit Diagrams

KLM-480 Circuit Diagram

KLM-481 Circuit Diagram

8. CHECK AND ADJUSTMENT PROCEDURE

Power Supply, Clock Board, and Joystick Checks

Procedures for checking and adjusting power supply, clock board, and joystick.

KLM-508/476 Amplitude and RESET Checks

Procedures for checking amplitude limits and RESET on KLM-508/476.

DCO1 and DCO2 Checks

Procedures for checking and adjusting DCO1 and DCO2 parameters like octave, waveform, and PW/PWM.

VCF Resonance and Cutoff Checks

Procedures for checking and adjusting VCF resonance and cutoff frequency.

EG Checks

Procedures for checking EG mode, attack, decay, sustain, and release.

VCA and MG Checks

Procedures for checking VCA gain, mixing level, and MG modulation parameters.

Total Performance Checks

Procedures for final output level, headphone, and battery checks.

Tape Interface Operations

7. SETTING CHARTS

Program Setting Charts