DECcolorwriter 1000 Color Printer

This Service Manual for the DECcolorwriter 1000 Color Printer provides comprehensive instructions for qualified service personnel on verifying operation, troubleshooting, repairing, adjusting, and maintaining the device. It covers the printer's general information, installation procedures, host connection verification, key operator training, detailed theory of operation, extensive troubleshooting guides, cleaning and maintenance routines, Field Replaceable Unit (FRU) disassembly/assembly, and specific checks and adjustments. Appendices include FRU lists, test patterns, and wiring diagrams.

The DECcolorwriter 1000 is an Adobe PostScript Level 2, thermal-wax transfer color printer operating at 300 dots-per-inch. It supports A- and A4-size media, features a 16-MHz RISC image processor with 8 Mbytes of RAM, and offers parallel, RS-232 serial, and LocalTalk connectivity. A unique 4-pass plain-paper printing process includes a special precoat for optimal wax adherence.

The manual details the printer's internal mechanisms, including the sequential thermal transfer printing technology, the roles of the engine control board (CPU, data controller, heat controller with dot compensation, thermal head controller, mechanical controller), and the image processor's graphics pipeline (I/O serializer, PostScript interpreter, rasterizer, engine driver). It also explains the paper path operation, from pick-up to printing and unloading.

Troubleshooting encompasses system power-up sequences, print engine diagnostics using internal test patterns, power supply checks (voltages, fuses, safety interlocks, motor resistances), and resolutions for common issues such as media jams, paper-pick errors, paper-clamping problems, print-eject jams, and various print quality defects like streaks, uneven color, or image offsets. It provides guidance on interpreting front panel LED error codes and utilizing rear panel DIP switches for self-diagnostics and configuration. Maintenance instructions specify cleaning procedures for critical components like the thermal head, rollers, drum, and sensors, along with lubrication guidelines and inspection for wear on parts like gears and belts. Comprehensive disassembly/assembly procedures are provided for all major FRUs, from cabinet panels and various motors to circuit boards and memory modules. Calibration procedures for thermal head temperature, pitch, drum belt tension, and paper clamp settings are included to ensure optimal print quality and performance.