28DavesLater

@28daveslater.bsky.social

previously Cripple Mr Onion on twitter. Noodling on retro stuff and working on my running. I occasionally work on movies and tv shows and stuff.

Currently editting a supercut of all my footage of reversing the SwanCrystal 8 mins so far at 400% speed (mostly) and I'm only just getting close to the sanding back the board part. Should I do it as one 25 min video or break into 2 or 3 parts?

Davinci Resolve interfsce showing an edit of the SwanCrystal recerse project. A closeup of the Sphinx2 chip is on screen.

Needed a mostly working Wonderswan / SwanCrystal to be able finalise the reverse pcb Ive been worling on. This one came up, listed as defective. Thanks to @asie.pl amazing knowledge there was a good chance it was just corrupt EEPROM data making the screen misbehave.

Atari 1040STE case that is very yellowed. Never seen a tide line like this though on the underside. It's out in the sun but the UV index is only expected to get to 4 today for a few hours so I dont expect it to do much. Was more about drying it after a cleaning. Might try properly in summer.

A very yellowed Atari 1040STE top shell sitting in yhe sunshine.A closeup on part of an Atari 1040STE bottom shell. There is a distinct line between a vey yellow area and grey area.

WonderSwan power daughterboard. As I'm getting closer to finishing this SwanCrystal reverse I'm getting some suggestions that I should attack this one next. You know, for completionist sake.

A Wonderswan DC power board front viewA Wonderswan DC power board back view

I think the SwanCrystal reverse is done aside from cosmetic stuff and maybe adding couple of touches to the silkscreen. I might branch it to modify the button pads slightly. Schematic can still be improved as certain components internal function gets figured out.

A KiCAD 3D PCB render of a SwanCrystal board front viewA KiCAD 3D PCB render of a SwanCrystal board rear viewKiCAD PCB editor showing a SwanCrystal board front view with major nets colourised.KiCAD PCB editor showing a SwanCrystal board rear view with major nets colourised.

The SwanCrystal schematic and PCB reversal can now properly begin. Slow process to get to the stage I've been most looking forward to. A bit of a skill leap required but also new fun things to learn.

a KiCAD PCB layout showing a Sphinx2 CPU, Cart Connector and a 1x30 fpc connector overtop of a scan reference image of a SwanCrystal PCBA KiCAD schematic showing a Sphinx2 CPU split into 2 units. Some connections exist between a cart connector and CPU unit A. Unit B and a 1x30 connector sit unconnect3d to the side.

I've never been into the retro PC side of things but an Atari made 8088 (PC3) was too good to go past. Listed as not working it shows some decent signs of life even if it can only find a portion of the RAM. Will be a slow burn project including hopefully adding a picoMem in future.

An Atari PC3 computer sitting atop a table, on a colourful towel.A commodore 1084 monitor showing the boot screen for an Atari PC3. A 301 error (no keyboard) is shown along with 256 KB Memory Good. A closeup shot of the RAM area on an Atari PC3 motherboard. All the RAM including the optional additional 128K is populated.

Acorn 28-AKF40 monitor connected to my Amiga 500. This monitor only does rgb analogue via a D9 connector. It's basically a stripped back 1084S-P1 with no composite or chroma luma circuit. Had to make my own cable up which onviously meant making backwards to begin with.

Turrican splash screen displayed on an Acorn 28-AKF40 monitor.

Tales from the bench. 2 repairs today apparantly "not working" The breadbin had an intermittent failure eventually narrowed down to a cold joint or micro fracture of the trace in the IRQ line. The 64 C worked perfectly but not for much longer as some mystery corrosion was taking hold.

A Commdore 250425 motherboard.A series of traces with through hole pins sticking up. A hint of subtle corrosion can be seen near some pins.Corroded green gunk looks to be dissolving a trace and covering the legs of an IC on a green and gold coloured morherboard.a green and gold coloured C64C shortboard - 250469 Rev 4 motherboard.

Attempting a repair on a Commodore 1901 monitor - it work but only in greyscale. Pulling it apart today and it's looking like sombody plugged something bad into the rgbi connector in its past.

A PCB with scorched and blown resistors.
A PCB with a missing large trace that connects to thr ground planeA PCB connected to a DB9 female port with several missing tracesA PCB with several bodge wires and a large missing trace.