Tom Stepleton

@[email protected]
563 Followers
150 Following
655 Posts
AI research engineer, glider pilot. Apple Lisa power user. Most of my posts will be about old computers; occasionally I'll mention flying.
Codeberghttps://codeberg.org/stepleton
Obscure 1985 BSD workstationhttp://mg-1.uk
U.S. call signWSØATO
Tom Stepleton1d ago
You want: a regular #Ethernet MAU to plug into an AUI port
You have: a MAU that only works with Apple's weird AAUI port
No problem! Here's an adaptor.
Tom StepletonFeb 21

Do you have 5.25" and 8" floppy disks that are spare, low-quality, degrading, or just generally in bad shape?

I'd like to take my floppy disk data recovery game to the next level. I have equipment, but there's no substitute for experience. Therefore I'm looking for loose collections of old floppy disks to practice on. I'm especially interested in working with disks where the binder affixing the media to the donut is starting to fail.

I'm in London; will pay shipping; can pick up disks around here as well. Boosts are appreciated!

Tom StepletonFeb 14
Meanwhile, the #PERQ has broken once again. A problem somewhere on the EIO board again, affecting floppy and hard drive both, but only after some data have been loaded from them. DDS=157 or 158 on HDD or FDD boots of POS respectively. PERQs gonna PERQ...
Show threadTom StepletonFeb 14
The double-decker Frankenfuse fits safely into the fuse holder and the little door still shuts! And best of all, it all works! Multiple power-cycles and it hasn't blown yet.
Tom StepletonFeb 14
"So it keeps blowing these 1A 250V slow-blow fuses I've got" ... "Have you tried a different make of fuse?" ... "Well, I've got some, but they're the wrong size"
Show threadTom StepletonFeb 10

More things it is not, as my campaign of disconnecting things wears on:

  • The AC fan
  • Anything on the secondary side beyond the rectifiers
  • The power switch

About the only things left to cause the intermittent failures are the transformer and the A/C line filter, strangely.

Tom StepletonFeb 9

Definitely riding the struggle bus trying to fix this #Tektronix 4907 power supply. A pretty simple linear supply that blows a fuse 33% of the times you turn it on.

Things it's not:

  • Any of the loads
  • The two saltshaker-sized bulk capacitors
  • The crowbar on the +5V rail

Find the schematic on page 208 of this PDF if you'd like to play along...

Tom StepletonFeb 5
Chris HansonFeb 5

I’ve published my Lisa filesystem access tool: https://github.com/eschaton/lisafs

It lets you list and extract the files in a Lisa filesystem, with automatic text file conversion. It supports both the flat Lisa OS 2.0 and the hierarchical Lisa OS 3.0 filesystems.

Right now it only works with Disk Copy 4.2 disk images but should be straightforward to extend to any other format that preserves page labels, e.g. raw 536-byte/sector ProFile dumps.

Open Source, MIT license.

#lisa #retrocomputing #opensource

Tom StepletonJan 30

Holy heck, setting up a Linux VM under #OpenBSD is no picnic for a noob!

  • Use Alpine? Recommended and it works for lots of folks, but the Alpine virtual image speaks ethernet... differently, probably some virtio thing. Couldn't ever get it to work.
  • Give up and use a Debian cloud image? OK sure, but you have to translate Debian's qcow2 into a qcow2 that vmm likes
  • Level 3 of the quest is getting your tightly locked-down pf config to open up juuuust enough for NATting traffic in and out of the VM.
  • More faff awaits from here!

All's to say that I really do hope immich is absolutely spectacular. I look forward to finally getting it working in 2027.

Tom StepletonJan 29
Maybe I should drop everything, get a better camera, and make a @tubetime -esque photo book called "BODGE"