Table of Contents Page
Service Guide ML390/391
0 About This Manual
Front Cover 1
Manual Copyright 2
1 Product Specifications
1.1 General Description - General Information 3
....1.1.02 Compatibility - Microline 390/391 vs. Microline
390/391-Plus
4
1.2 Product Specifications 5
1.3 Paper Specifications 6
1.4 Physical Specifications 7
1.5 Power Requirements 8
1.6 Environmental Requirements 9
1.7 Agency Approvals 10
1.8 Options 11
1.9 Consumables 12
1.10 Memory Specifications 13
1.11 Reliability Specifications 14
2 Principles of Operation
2.1 Printer Overview - General Information 15
....2.1.02 Compatibility - Microline 390/391 vs. Microline
390/391-Plus
16
2.2 Circuit Board Description 17
....Block Diagram (Microline 390/391) 18
....Block Diagram (Microline 390/391-Plus) 19
2.3 Electrical Operation - Initialization 20
....2.3.02 Interface Control 21
....2.3.03 Print Head Drive Circuit 22
....2.3.04 Spacing Operation 23
....2.3.05 Line Feed 24
....2.3.06 Alarm Circuits 25
2.4 Mechanical Principles Of Operation - Printhead 26
....2.4.02 Space Mechanism / Operation 27
........Head Gap Adjusting Mechanism 28
............Head Gap Adjusting Mechanism - Diagram 1 29
............Head Gap Adjusting Mechanism - Diagram 2 30
....2.4.03 Ribbon Drive Mechanism / Operation 31
....2.4.04 Paper Feed Mechanism 32
....2.4.05 Paper-End Detection Mechanism 33
....2.4.06 Semi-Automatic Sheet Feeder (SASF) Operation 34
....2.4.07 Release Lever Operation 35
3 Maintenance & Disassembly
3.1 Maintenance - General Information 36