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Recent content by SuperSVGA

  1. SuperSVGA

    Any fix for the ImageWriter color ribbon gear?

    Someone on Reddit recently posted a fix they did using rubber o-rings.
  2. SuperSVGA

    Macintosh SE/30 logicboard recreation (thread revival)

    You can, you just have to use Standard assembly which costs more.
  3. SuperSVGA

    Mac Portable Issues with ZuluSCSI

    The adapter provides power to the ZuluSCSI via the termination power on pin 26, supplied via the diode connected to +5V.
  4. SuperSVGA

    Apple /// restoration

    That sounds right, though it sounds as if your capacitor is draining a bit in between tests, which is probably normal to the spec of capacitor you used to test. It's not the most accurate test either, but it at least verifies basic functionality of the capacitor.
  5. SuperSVGA

    Macintosh Portable M5120 Repair Tips

    All of that sounds normal. 1 Amp is typically good enough to run without the hard drive, but I typically see the total draw of the system around 2.5 Amps when the hard drive first spins up. Was the computer running? There's quite a few different variables here, so it's hard to say which is at...
  6. SuperSVGA

    Macintosh Portable M5120 Repair Tips

    Yes, connect the bench power supply to the battery terminals or the 4-pin connector on the board. If you connect to the battery terminals you will need to have that switch pressed down. If your wiring allows there's a few different gaps where you can have the wires come out while the battery...
  7. SuperSVGA

    Apple /// restoration

    You can do a basic test to see if it's working at the very least. Remove the capacitor from the board and set your multimeter to test resistance. Short both ends of the capacitor, then test the resistance across it. It should very briefly show high resistance increasing then show overload or...
  8. SuperSVGA

    Macintosh Portable is suddenly flaky / unstable, not sure what's up

    It's not a great solution, but if you drill a hole at the end of the crack it will stop spreading. I've tried super glue, but it didn't hold and discolored the inner surface where the signatures are.
  9. SuperSVGA

    Apple /// restoration

    If possible, remove it from the board and test it with the capacitance setting on a multimeter if you have that available. Or just replace it if possible. I just put together the main clock circuit since it's not too complex: You can also see a similar effect in a circuit simulator, but this...
  10. SuperSVGA

    Macintosh Portable M5120 Repair Tips

    You could likely copy it, I'm not certain if it needs some sort of extension as well, I'll have to look later. It may vary based on what system version you copy it from, try the one named "Portable" or something as well. You shouldn't use a PowerBook charger with it, as it may supply too much...
  11. SuperSVGA

    Macintosh Portable M5120 Repair Tips

    The system disk you're using is probably the bare minimum to run the computer, it doesn't have most extensions and other things you would get from the installer. You may need to use install disks and install to a floppy disk to get the proper system extensions. What you're describing with the...
  12. SuperSVGA

    Macintosh Portable M5120 Repair Tips

    Do you have the Brightness control in the Control Panels? If you don't have the right system software installed, the backlight usually won't come on. Here's System 7.1 for example:
  13. SuperSVGA

    Apple /// restoration

    I did some more experimenting, and I think you should check C23. I was able to replicate what you're measuring in the clock section by removing C23 from the circuit.
  14. SuperSVGA

    Mac Portable Issues with ZuluSCSI

    Which Portable do you have, the M5120 or the M5126? Do you have a multimeter to check the voltages at the molex power connector of the adapter, with the ZuluSCSI disconnected?
  15. SuperSVGA

    Apple /// restoration

    Most of those look fine. Looks like you're getting a good supply voltage and the voltage divider resistors are working fine. I think the tricky part is there's both an earth/shield ground and a signal ground, so if you're referencing earth ground you might not see 0V on the signal ground. If...
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