Having experienced exploding paper foil, like Tezza with his Osbourne
, and not wishing to let that "magic smoke" escape from mine, I have been proceeding with caution and will replace every electro and paper foil cap in the psu.
Using my bench supply, the main logic board and disk drives have been up to 5v, and I have had the display module running on it's own, with raster present, all without incident so far.
The PSU is still waiting on the next batch of caps to be ordered - RS Components is my usual source.
Matching the original electrolytic's is tricky, as they are all now obsolete. I did find some data to help pick a suitable replacement, but mostly guess work.
After much effort and search engine disappointment, I finally have schematics and parts lists for everything, including the PSU and monitor.
So progressing nicely so far.
One thing I can try out later is my recent purchase, an HxC floppy emulator, which will apparently does work on an Osbourne 1 with an adapter cable.
The size difference in the modern equivalent is quite considerable.
I haven't been able to get a spec sheet for the older one to compare the rated life.
The X2 rated filter caps were definitely the worse for their age, and would have died in exciting ways.
The visible cracks are the danger sign, and have been replaced with new items the same type, and size.
So the Osbourne 1 now has been powered up fully without incident, however, there is now a logic board issue to resolve before I can progress further.
I have garbage on the display and the buzzer, so on to the next stage of troubleshooting the issues.
This one the later "Blue front" version, with a date label sticker in the power bay for 23-12-82.