• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

Recent content by Jagmn

  1. J

    Repairs, on-board RAM and 475 / 575 boards

    Very nice :cool: Will you make a variant that can take a LTC1799 for overclocking? Like a built-in Spicy-o-Clock?
  2. J

    Repairs, on-board RAM and 475 / 575 boards

    Well that's fun :) Is this the near-conclusion of a recent project?
  3. J

    Repairs, on-board RAM and 475 / 575 boards

    The one I repaired most recently had some (impossible to visibly locate) broken traces between MEMCjr and the SIMM / on board RAM. The symptom for me was that it 'bonged' fine without a SIMM but did not boot, yet gave death chimes with the SIMM installed. After a lot of buzzing around with my...
  4. J

    "Power Macintosh Card" and "601 Processor Upgrade" - What is the difference?

    I've recently acquired an Apple 601 (50/66Mhz) card in a bombed 475. Does anyone have schematics for these? I'm probably going to have a go at overclocking a 575 and 475 with/without the upgrade card.
  5. J

    LC575 no screen crash chime

    My 575 boots fine without the on-board RAM, though I've only booted it from a BlueSCSI so far.
  6. J

    LC575 no screen crash chime

    Congratulations! Yes; the routing can be a pain. I have occasionally used needle probes to find a closer VIA or other piece of track that is more convenient (with the usual faff of trying to solder it).
  7. J

    LC575 no screen crash chime

    Have you checked the data and address lines to the SIMM? I’ve had 2 boards where some of these were corroded out. The signals are shared with the on board RAM so just removing that won’t necessarily help. The 475 I just ‘fixed’ had some traces broken on the address lines both between the SIMM...
  8. J

    Repairs, on-board RAM and 475 / 575 boards

    I have now 'repaired' two boards (one each of a 475 and a 575) where some/much of the data/and/or/address lines under the on-board RAM have been destroyed. In both cases, I've been able to get enough bodge wires in place to be able to get the boards booting without the on-board RAM (just enough...
  9. J

    Can this 575 logic board be saved?

    Hi Terry, sure. I've cleaned up my notes and included them below. Apologies for the random way I did the pin counting.
  10. J

    Bombed SE/30: Is it dead, Jim?

    Sorry, the boards hadn't fully dried out from the IPA when I took those.
  11. J

    Bombed SE/30: Is it dead, Jim?

    Thanks for the input, folks. This is the board after 1 round of vinegar, soap + IPA. There's still all lot of battery muck underneath the '030 and a few other chips. I'll have a go at desoldering the '030 to clean up underneath but, given the corrosion through some of the holes / along the...
  12. J

    Bombed SE/30: Is it dead, Jim?

    Thanks for the input, folks. I'll see what it looks like with the muck cleaned off but I'm not hopeful. I've still got a fair amount of IPA etc from bringing two Classics (I and II) back to life. As for the rest of the SE/30; I'm wondering about holding out for a working LB versus attempting...
  13. J

    Bombed SE/30: Is it dead, Jim?

    I recently acquired a known dead SE/30 (my first such machine) and, as expected, the battery has done a thorough job on the logic board. Usual suspects, from what I can tell: Rotted out VIAs, some of the '030 pins have been corroded through the board and who knows what else. And, oh yes, very...
  14. J

    3D-Printed Objects

    That’s the one!
  15. J

    3D-Printed Objects

    Hi Folks, As part of a conversation with @JDW, I'm uploading a 'tabless' version of this speaker case. The reason being that, if you printed a tabbed version for the CC stereo mod, the tab crosses into the larger area of the original CC speaker and makes it hard to fit everything together. This...
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