LA310 MultiPrinter

This document is the Service Guide for the LA310 MultiPrinter, published in October 1992 by Digital Equipment Corporation. It provides comprehensive information for servicing and maintaining the LA310, a low-cost, wide-carriage, 9-wire dot matrix printer designed for business applications.

The guide covers:

• Overview: Describes the printer's features, including flexible paper handling (single sheets, continuous forms, multi-part forms, labels, envelopes), serial and parallel interfaces with automatic switching, support for multiple protocols (DEC PPL2, IBM Proprinter III, Epson FX-1050), optional cartridges, various print modes (HSD, NLQ1, NLQ2, Quiet), and built-in self-test diagnostics.
• Installation: Details precautions, unpacking instructions, physical setup, and extensive guidance on paper loading, including various paper types, weights, printable areas, and the use of paper handling devices like guides, feed knobs, levers, and optional tractors. It emphasizes adjusting the print head distance lever based on paper thickness and copies.
• Set-up: Explains how to enter and navigate the printer's set-up mode using control panel buttons, allowing users to print current configurations, change settings (e.g., error beep settings), save new values, and recall factory defaults. It also covers optional emulation selection.
• Tests & Diagnostics: Outlines a range of self-tests and diagnostic modes, including power-up diagnostics (ROM, RAM, NVR checksums), alignment tests ("H" pattern, print head pattern, PLU/PLD), carriage motion tests, paper sensor adjustment procedures, and service tests such as printing self-tests and serial/parallel port loopback tests to identify malfunctions.
• Troubleshooting: Provides general troubleshooting rules and specific solutions for power-related, operation-related (e.g., paper feed issues, printer stopping), print-related (e.g., faint print, alignment problems, paper jams), and ribbon/carriage-related issues.
• Remove Replace: Offers step-by-step instructions for removing and replacing Field Replaceable Units (FRUs), including the printhead, covers, internal console, mechanical assembly, printhead cable, main board, power supply, and power supply fuse, with warnings about safety and subsequent adjustments.
• Cleaning: Recommends routine cleaning to prevent clogs from dust, dirt, and ribbon residue, and specifies procedures for cleaning the platen.
• Appendices: Contains detailed printer and paper specifications, a list of spare parts, set-up configuration menus, and various block diagrams and schematics for the internal components.

The document is intended for trained personnel due to the nature of the procedures involving system covers and internal modifications.