Digital AlphaStation 200 4/166

This document outlines the procedure for upgrading a Digital AlphaStation 200 series workstation to a model 4/166. It covers:

• Required components: Identifying the contents of the upgrade kit (PAL chip, oscillator, medallion, antistatic strap, etc.).
• Preparation: Safety steps including backing up data, shutting down the system, and using an antistatic wrist strap.
• Hardware modification: Detailed physical instructions for opening the chassis, removing the drive bracket, replacing the IRQ PAL chip, replacing the oscillator, and applying a new model label.
• Troubleshooting: A table of common issues encountered post-upgrade and a detailed reference table for decoding diagnostic LED light patterns.