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  1. apm

    Radius Pivot on SE/30

    I'm running 7.5.3. It's been a while since I used the card, and at the moment I don't have any drivers installed (they may have been lost when I switched from a failing hard drive to SCSI2SD). But I do recall that it worked, though I could never get the pivot function to work. 
  2. apm

    Radius Pivot on SE/30

    I've got a Color Pivot SE/30 card -- similar form factor but different layout, and all VRAM soldered. It's got ROM v2.4. I can dump and share the image if anyone wants it.
  3. apm

    SE/30 replacement parts

    Looks right.
  4. apm

    SE/30 startup issues

    You'll need to recap the board soon, but this sounds more straightforward: the hard drive is likely dead. It's very common for these old drives to fail. SCSI2SD is a good modern solution, not only more reliable but quieter, lower power, and with greater storage capacity.
  5. apm

    signs of dead flyback transformer? Mac Plus issues

    It's not clear whether the floppy problem is related to the video problem or not. Booting with an external SCSI drive or a Floppy Emu would clarify. But it may well be a separate issue. If you look closely at the photo, you see that every 4 lines of the picture are duplicated, and every other 4...
  6. apm

    signs of dead flyback transformer? Mac Plus issues

    Looks like a logic board issue. Does it boot? What does the screen look like as it boots?
  7. apm

    Help with troubleshooting a Plus

    0F000D is the code you should get when hitting the interrupt button, not the reset button. (Can you confirm if you get that code when hitting the interrupt button?) If it happens when pushing the reset button, then something very weird is going on with the interrupts. I might look around the...
  8. apm

    More SE/30 Woes

    UA8-UD8 are the 74F253 chips. Some of the numbers will be manufacturing codes. "F253" is the important part. UE8-UG8 are all involved with video. They shouldn't be the cause of your problem. UA8-UD8 are also video-related, connecting from the bus to VRAM, so I'm not sure I'd pull those off the...
  9. apm

    Compact Mac Screen Width Adjustment Tool

    I have used a wooden kebab skewer with some success. :)
  10. apm

    SE/30 recap – functional with checkered pattern

    Nice work! Great to see it working again!
  11. apm

    More SE/30 Woes

    It might be a problem with one of the RAM address lines (the upper ones that matter for 4MB SIMMs, but not 1MB SIMMs). If so, the most likely cause would be a rotted trace from the cap leakage. Perhaps check around the SIMM socket near C1 to see if anything is opened up there. In the schematics...
  12. apm

    Help with troubleshooting a Plus

    It could be a ROM problem, but I'd also wonder about a problem with interrupts and/or connections to the VIA chip. Guide to the Macintosh Family Hardware has some good info on how sound works on the Plus and earlier Macs. The CPU fills up a memory buffer which is played back automatically by...
  13. apm

    SE/30 recap – functional with checkered pattern

    Yeah, that does sound like a problem between the CPU and VRAM. Perhaps when it tries to read back the data in VRAM, it generates some kind of bus error because the address line is stuck in the wrong place. I'm not exactly sure of the mechanism there, but if the problem was on the video scan...
  14. apm

    SE/30 recap – functional with checkered pattern

    The pattern looks like 8 pixels wrong, followed by 8 pixels correct. In other words, 1 byte each: even numbered bytes wrong, odd numbered bytes okay. If it were UE8, you would probably see the same bit(s) in each byte faulty. The question is whether the problem is writing the data into the...
  15. apm

    SE/30: distorted picture

    I'd start with C9 on the analog board. It's the big electrolytic cap in series with the vertical deflection coil. The warped picture could be magnets if the seller messed around with them, otherwise I don't see how they would have gotten out of alignment. If those are still glued, and it's not...
  16. apm

    128k/512k/Plus analog board voltage adjustment

    I recapped the analog board on my 128k last week. Everything is running fine, but I am curious about the voltage adjustment. Since there's only one adjustment that affects all voltages, getting 5V set exactly to 5.00V on this Mac leaves 12V and -12V at 12.3V and -12.4V, respectively. The Mac...
  17. apm

    Macintosh Plus... Another Analog board issue

    Check the voltages? Especially 5V. The CPU may be more sensitive than the display logic.
  18. apm

    Macintosh Plus Voltage and Display "Static"

    Strange. The shifting pattern must happen because the video signal and the horizontal scan timing are getting out of sync with each other. Since the video signal is digital and can't shift continuously by sub-pixel amounts, that points to the horizontal scan jittering back and forth in timing by...
  19. apm

    Macintosh Plus Voltage and Display "Static"

    Can you post a photo or video? I would doubt it's a voltage issue, especially as 5V is at the correct level. I'm not sure -12V is used for much anyway. It could be a problem on the analog board or the CRT neck board though -- something in the video buffer circuits. Or I suppose it could even...
  20. apm

    Finally got an original Macintosh

    @james_w it did in fact come with a mouse (and keyboard), and I think it is the original square-connector type. But thanks! Also, now that I've got the external floppy drive it actually seems like a usable machine.  @ArmorAlley the question is, how long will it take before these vintage...
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