I attempted to test an LC last night since it appeared fairly clean and I didn't see cap goo on the logic board. I powered it on, floppy drive made some noise, but there was no startup chime. Powered down, tried reseating the speaker/fan assembly (this is an early LC with the fan and speaker in a plastic housing with friction-fit pins connecting to the logic board). When I powered back on, same thing, but about 15 seconds later I heard a loud bang from the PSU. Opened it up and found that a 4700pF Rifa Y cap connected across 2 pins of the IEC socket had exploded, releasing a lot of noise, an odor reminiscent of dead fish and cat urine, but thankfully no cloud of smoke or brown goo.
This was an Astec PSU dated early 1991, maybe it makes sense for people replacing bad electrolytics in these PSUs to change out these yellow rectangular caps too, they are a smaller version of the same capacitor that likes to explode on 128k/512k/Plus analog boards.
This was an Astec PSU dated early 1991, maybe it makes sense for people replacing bad electrolytics in these PSUs to change out these yellow rectangular caps too, they are a smaller version of the same capacitor that likes to explode on 128k/512k/Plus analog boards.
