Recent content by DevyDevly

Oh wow - a scan of a manual hold be awesome if it’s got any Accelerator II info. Searching for PowerCache I did find these… https://archive.org/details/DayStarCacheCardManual/page/n29/mode/2up https://archive.org/details/daystar-universal-power-cache/page/24/mode/2up

Many thanks for the info @Melkhior, Saving has started saving for some 74ABT651 spares - Mouser has them, but not cheap. I relatively new to the game so tend to focus of power, reset, address, and data lines. But thanks for helping me understand the importance of the DS and AS - another tool...

Hi All, Long shot, but does anyone out there have manuals, schematics, PAL dumps, or any doco around the Daystar 33/030 Accelerator II? Searching the web I’ve found very little info - even Daystar’s Internet Archive pages are sparse. A couple of ads and tests in MacWorld March ‘89 are about...

Gah - You’re so close! Great find on those broken traces. Maybe there’s just one other little wee bad connection - flexing or pushing on parts of the board might help you find it quickly.

Thanks @blturner :) I'm quite chuffed. If I had to bet on your issue I'd bet on another broken trace - to quote Wall Street Pros when reviewing a bad quarter "where there's one turd, there's many". And trying to follow traces on the top side, under chips and slots, can be quite tricky. I...

Sooo… turns out I had a broken trace (DSACK0 - data strobe acknowlege) from the NuChip (22) to the GLU (59). These data strobe signals seem to be quite important in getting NUBUS, SCSI, etc going - will definitely be a higher priority to check in future. Took me a while to find but got there in...

You latest YouTube post using the IR camera was very timely. I can’t believe those temps - especially those when powered off!

Thanks JDW - it’s good to get confirmation that it’s a tricky task to get an optimal fit and that I wasn’t missing something major (I’m relatively new to electronics and retro repair). I went for the best ripple specced caps (EKXE401ELL5R6MJ16S) I could find and went up to 5.6uF from 4.7uF (plus...

Sitrep: PSU and House intact. It sure looks weird but everything fired up ok and I let it run for 5 mins or so. Got to fix brokern traces on the Mac II motherboard now... Thanks @JDW for your SE/30 Sony PSU recap where you drill holes in the board for the big caps - it gave me the confidence to...

Thanks Gerry. I’ve purchased the best specced caps I can find (12000 Hrs @ 105°C; 100 mA @ 120 Hz; 250 mA @ 100 kHz). I can’t find the ripple specs for the original but can’t imagine they would be better than the best available today - unless there was a different subclass of cap that use to...

I share your pain @blturner with a Macintosh II with similar problems (820-0228-A) Occasionally I get an all grey screen and a reset (NMI) also gives me half a sad Mac. After a recap I've gone cross-eyed trying to find broken traces but only the one found so far (even with lots of candidates)...