Editing IBM 5100 Maintenance Guide (section)

== Opening the System Unit ==

Tools: Philips #2 screwdriver, T15 / T20 Torx (some fasteners), anti-static strap, high-voltage probe.

# Power off and unplug all cables (mains, BNC video out, communications adapter, printer).
# Locate the cover fasteners on the rear and bottom of the chassis. The 5100 uses a clamshell construction — the upper shell lifts off after removing the rear screws.
# Lift the upper shell carefully — '''the 5-inch CRT and deflection board are mounted in the upper shell''' and connected to the planar by cables. Do not yank.
# Inside (from rear to front):
:: '''Power supply''' (left rear) — linear PSU with transformer, bridge, bulk caps, series-pass regulators on a heatsink.
:: '''PALM processor board''' (centre) — the board with the 13 bipolar gate arrays.
:: '''Executable ROS''' and '''Language ROS''' boards.
:: '''RAM (RWS) cards''' — 16 KB modules.
:: '''DC300 tape drive''' at the front.
:: '''Keyboard''' on the front panel — separate assembly with capacitive sensing electronics.