This year for retrochallenge I am restoring
- My PowerBook Duo 2300c
This has failed with a slow sad Mac chime
- Fixing my rare school mini 286 Carry terminal PC
- Setting up a NT and AFP server for file sharing in my museum
- Setting up a real dialup internet with users names and passwords
In frustration I kept on turning on and off my Carry 286 and the stupid thing booted.
It would fail ram testing (or at least freeze) at various times during tests or use.
Once I got the machine going I was able to boot into DOS via an XT-IDE card and play leisure suit Larry 1 and AlleyCat!
I was playing for about 45 minutes. Turned it off and the unit went “pop”
The Fuse in the PSU popped.
Upon check with a colleague it seems possibly the switching IC died and it blew out a 340ohm resistor with it.
The struggle continues!
I have so far recapped the whole PSU but am yet to relate the resistor and IC
Unfortunately the colleague that knows switch mode power supplies ghosted me during the October month which lead me to be a little demoralised.
Due to illness and an Apple II event, I eventually at least got several of my PowerBook Duo computers recapped and cloned the hard disks onto a Blue SCSI unit Apple Disk Copy 6.3 to make bootable clones of the drives from each of my Duo’s for deep storage should a drive fail in the future.
I can also mount the Blue SCSI images in my Sheepshaver for sorting and assessment of files and Applications / configurations located during my restoration projects.
Specifically with my 2300 Rebuild - I had no luck. I have determined that it is likely the onboard RAM has failed and this has been put into the too hard basket for now - I have installed an alternative re-capped Main Logic board for the time being and this time around I have used Polymer capacitors for long term repair rather than tantalum.
I am always keen to not use tantalum on power circuitry due to the potential for fluctuations. I also like the original feeling of the Polymer caps I have used - albeit expensive - I should never have to concern myself with a failure in the future of the Main Logic boards.