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croissantking's conquests
Posted by: olePigeon on 2024-09-03 15:00:35 @Durosity "Shiiiiiiiiiiiiii-" "GI Joooooooe!" I believe the guys that created those went on to work for Cartoon Network.
Posted by: Daniël on 2024-09-04 05:06:18 Maybe with a slightly larger PCB, there could also be a regulator circuit for generating 3.3V, so the lower voltage MC68040V could be used. Disregard that, I skimmed the datasheets too quickly and didn't pick up on the fact that the V doesn't have an FPU either, despite no LC or EC naming convention being present 😅
Posted by: croissantking on 2024-09-04 05:07:08 Disregard that, I skimmed the datasheets too quickly and didn't pick up on the fact that the V doesn't have an FPU either, despite no LC or EC naming convention being present 😅 Yes, it’s a bit misleading!
Posted by: croissantking on 2024-09-21 11:47:28 Got some bits and pieces off eBay to tinker with. - Untested Beige G3 board with surprise 750L/350MHz upgrade. - Performa 631 board with QFP 68LC040 on a PGA interposer. - 32MB FPM RAM module with 60ns TSOP chips suitable for maxxing out a PowerBook 500 series (or similar contemporary machine) RAM card. Check out the 040 on the interposer. It looks like a simple 2-layer board. It has some interesting markings on the underside: AMP 560633-1, 511-0063. The date code is in line with many of the other chips on the logic board, so it could have come onboard from the factory. The Valkyrie chip has an even later date code of 9546 – well after the Performa 631 had stopped being produced, so maybe the board was a service part? I plan to solder one of my 'full fat' QFP 040s onto the interposer and see how it goes; it may even find itself a new home in my spare 840AV board if I ever get that fixed. I would also like to redraw this design in KiCad and share it with the community so that anyone who wants to in future can convert a QFP to PGA. I don't know how I would recreate the pins, however, can anyone suggest how this would best be done? The Performa 631 board is badly damaged in one corner due to a battery leak. I'm not sure what to do with it, yet. (Anyone interested in one for a project?)
Posted by: LaPorta on 2024-09-21 15:00:20 Battery leak? Those square rayovac things leak? Never seen that.
Posted by: 3lectr1cPPC on 2024-09-21 15:39:26 They’re Alkaline - if anything, it’s surprising that they’re only just now starting to become a problem.
Posted by: croissantking on 2024-09-21 16:43:33 Battery leak? Those square rayovac things leak? Never seen that. They’re Alkaline - if anything, it’s surprising that they’re only just now starting to become a problem. That’s interesting. I’d just assumed they leaked like other PRAM batteries based on what I’m seeing on this 631 board.
Posted by: Durosity on 2024-09-21 17:23:53 Yeah I’ve not seen many of the square ones go until recently, but I’ve now seen at least 3 this year so I guess they’ve started reaching that point in their lives.
Posted by: 3lectr1cPPC on 2024-09-21 18:14:42 Somewhat unrelated, but I opened my PM5400 up a few weeks ago to check if someone had pulled the original battery (it had been fully maxed out, including an SSD so I assumed a previous owner did). They did, and replaced it with a 3-AAA holder - great, but they mixed battery types. Two were energizer lithium, the third was an off-brand carbon zinc, which was leaking. Glad I got that checked and dealt with. No damage thankfully.
Posted by: croissantking on 2024-09-21 23:19:33 The CPU on the interposer boots up an 840AV - to a flashing ? at least - I name it the Macintosh LC 840, or Performa 840CD, depending on which market it was designated for. 😉
Posted by: croissantking on 2024-09-21 23:51:05 I sprayed my 840AV’s 3D-printed CD-ROM bezel using Rustoleum Stone Grey which I saw that @jmacz had used for one of their projects. I was initially just going to leave it as a white resin colour, but it started to yellow in patches and looked horrible. Somehow the yellowing on the Quadra itself doesn’t bother me as much. It’s come out a lot darker than I imagined, but it’s better than it was before at least. The shade is different enough that it looks intentional rather than a bad colour match, and it looks more premium as well. The machine could be a candidate for either a retrobrite or a full respray, but I’m leaning towards just leaving it as-is. I installed an auto-inject floppy (with the correct sled) that I got off eBay for cheap as untested, it works great after a full service. It had a manual insert drive in there before which wasn’t suitable for the bezel. (Side note: I love those F75W drives). I also stuck an ATX PSU inside the case so I can actually use the computer with the case closed for the first time.
Posted by: joshc on 2024-09-22 01:13:14 Nice machine, I'd vote for not painting or retrobrighting personally and I think the bezel looks alright. There is a colour that would be a closer match, I think @cheesestraws knows what it's called.
Posted by: Big Ben on 2024-09-22 01:54:54 Woah, this bezel looks like a injected plastic piece, fantastic work! It may be a bit yellowed but it’s still looks great imho.
Posted by: croissantking on 2024-09-22 03:45:03 It looks a little different under daylight. Woah, this bezel looks like a injected plastic piece, fantastic work! Ahh thanks, you are too kind! I’d chalk it down to the detail you get with a resin print plus the right technique for the spray paint job.
Posted by: Fred1212 on 2024-09-23 00:00:08 Like it!
Posted by: MacUp72 on 2024-09-23 01:30:57 yeah, that Macintosh off-white.. maybe you could give this simple primer spray a try, turned out quite ok with my 190c..
Posted by: croissantking on 2024-09-23 04:49:38 If I got the colour right, would there be any interest in 3D printed Quadra bezels?
Posted by: KC13 on 2024-09-23 08:24:15 Yes!!
Posted by: Big Ben on 2024-09-23 14:58:03 If it’s compatible with a PM8100, I might be interested. Got several damaged ones.
Posted by: croissantking on 2024-09-23 15:21:42 If it’s compatible with a PM8100, I might be interested. Got several damaged ones. Yeah, it’s the same bezel.
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