RAR archive for the IBM ThinkPad A20 and A22 notebook family, weighing 2.82 MB. Nothing in the name identifies a board number, revision or the exact files packed inside, so inspect the contents once extracted. Material for these older ThinkPads is generally used to trace power supply circuits, verify component values and locate test points when restoring a board that will not start. Extract with any common archiver such as 7-Zip, and confirm the planar markings on the PCB match the drawings before relying on measurements or replacements.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.