Apple Macintosh Plus - S/N F82749PM0001A
28 August 2016
Plus crackles, emits smoke
After the system is powered on for some time, a crackling noise is heard and smoke issues forth, most of it from the lefthand top vents. The system appears to continue operating normally in the time it takes to switch it off.
C38 on the analog board has failed. Replace it. Component is 0.1µF 250V film capacitor, with 20mm lead spacing and X2 safety rating.
HD20 not recognized
Plus does not boot from HD20, nor is HD20 recognized when booting from the HD20 Tools diskette.
The Apple HD20 is apparently incompatible with the Brainstorm Accelerator Plus. The Brainstorm accelerator is permanently fixed to the logic board, but the HD20 works normally if the logic board is replaced with an unaccelerated one.