Editing Osborne Vixen Maintenance Guide (section)

== Common Failure Points ==

=== PSU Failure ===
* No power, unstable voltages, or burning smell.
* Replace all electrolytic capacitors and check for cracked solder joints.
* Inspect switching transistors and diodes for overheating.

=== RAM & ROM Socket Issues ===
* Intermittent boot, random crashes, or garbled screen.
* Reseat RAM (usually 4164 or 41256 DRAMs) and ROM chips; clean pins and sockets.
* Replace sockets if contacts are loose or green.

=== Floppy Drive Faults ===
* Failure to read/write, constant seeking, or “NO BOOT DEVICE” errors.
* Clean heads, check drive belt (if fitted), and inspect power to drive PCB.
* Replace tantalum/electrolytic capacitors on drive logic board.

=== CRT Display Problems ===
* Dim, flickering, or distorted video.
* Check video output voltages, inspect CRT neck board for cracked solder joints.
* Replace CRT only as last resort; check flyback transformer for arcing or noise.

=== Keyboard Issues ===
* Stuck or dead keys, repeating characters.
* Clean key switches with contact cleaner.
* Inspect and repair keyboard matrix traces if rows/columns are missing.