Recent content by Garrett

  1. Garrett

    IIci PSU - Dead as a Dodo

    Step 1 is to check the fuse. If it's blown, I'd be suspect of surrounding components. I had one that blew, but was actually caused by a blown MOSFET, meaning just replacing the fuse would immediately blow it again. Troubleshooting can be tricky, but it's absolutely possible to do with enough...
  2. Garrett

    Color Classic Flyback Replacement from LC5xx

    Great observations - thanks for sharing. Good to know there are workarounds to make that flyback more usable. Sounds like AB/flyback longevity may be a concern if left to run like that though.
  3. Garrett

    2400c hard drive issues

    This happened to me once on a 2400c, and it turned out to be a bad IDE connector on the logic board itself. I think a pin was broken off. Not sure how that happened, but bodging it restored full functionality!
  4. Garrett

    AppleCD SC Teardown and Troubleshooting: Sony CDU-8001 Drive

    I'm fascinated by this observation. What you see pictured is exactly how it came out of the case, so if it's really swapped, that means someone has been in the drive prior to me. I'll have to look closer at the PCBs and correct this issue. If it magically starts working, I'll be sure to post...
  5. Garrett

    IIfx Parts Machine Repair - RAM, ROM, Power on/off Fixes

    Another great writeup, David! This seller had two of these listed - I picked up the other one he had. Like yours, it also appears to have been a user-upgraded machine, but didn't have the fun "custom" sticker on the front face. Mine was listed as "bad power supply," but spoiler alert the power...
  6. Garrett

    PowerBook 100 RAM Expansion Pinout - New RAM Card Build Issue

    I decided to revisit my issues with this RAM card once again. I thought I could be clever and connect the PowerBook to my newer Mac and use Serial Diagnostics, but I can't get it to talk with my new Mac at all. The Sad Mac error I get is 0000000F 00000002, which doesn't seem RAM related based on...
  7. Garrett

    Delve into Reconnaissance - and fixing my Mac IIcx

    I've had a few troubled boards I've been putting off working on. This past March, my motivation to do something with these boards increased! This was due to the wonderful new Reconnaissance application, developed by @jack 68k. First up was an SE/30 with some boot issues. Reconnaissance informed...
  8. Garrett

    PowerBook 180c TRACKBALL Repair Help Needed

    I’ve had this issue before, and found that it’s made worse by cleaning the blue rollers with IPA. They’re slipping on your metal shafts. Now any PowerBook I work on automatically gets new silicone rollers. If I recall, you’ve done this job to your Macintosh Portable. Good news- the PowerBook...
  9. Garrett

    Dynamic Engineering Portable PDS RAM Card

    Wow, this is so cool! Thanks for posting. I suppose a card like this could be recreated, if it weren't for the missing PLD code.
  10. Garrett

    Dynamic Engineering Portable PDS RAM Card

    Great work! I saw this card on eBay as well - glad someone here snatched it up. Looks like the same RAM ICs that the PowerBook 1xx series uses. Did you have to tinker with the jumpers to get it working? I wonder why Dynamic Engineering didn't use the dedicated RAM expansion connector, but rather...
  11. Garrett

    Macintosh LCII failure

    That's interesting that when swapping DFACs, the issue stays with the board, not the sound chip. I had an LCII with bad audio once, and replacing the DFAC did solve my issue.
  12. Garrett

    LC575 computer killed LC520 motherboard! 😭

    Hi James, here's another idea. I once had a Color Classic board which would power up, but never "bonged" or displayed an image. The fix in that case was removal of both ROMs, scuffing the legs of each, and reinstalling them into their sockets. I've had to do this trick with a couple of LCIII...
  13. Garrett

    Mac IIci cache card

    See my post in this thread. I included a few benchmarks from the Apple Diagnostics application. https://tinkerdifferent.com/threads/iici-cache-card-three-tone-chime.2798/#post-27601
  14. Garrett

    Identifying mystery macintosh SE Accelerator/upgrade card

    That's the first time I've ever seen a 68EC030 in use on a Mac. Was the lack of MMU acceptable on a machine that shipped with a 68000 CPU? Unsure if that's the cause of any issues but interesting to see nonetheless.
  15. Garrett

    Color Classic Flyback Replacement from LC5xx

    Are you using the High Res or VGA modded analog board? That may factor into the types of adjustments available. I've only ever done the 68V VGA mod myself and haven't run into this issue. Generally, people seem to have trouble setting the horizontal width as it should, so I'm surprised it's the...