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redruM69

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  1. Oh well hey! Even better! I didn't know it was updated.
  2. @alaska360: Your Mac Portable battery v3.0 model has a couple of minor errors that can cause slicing issues, and a weak print. 2 of the 4 corners on your outer box have disconnected shells, which caused those 2 corners to print as if they are free standing. I fixed it. STL download below. portabattery30(FIXED).stl
  3. I threw in the towel and shipped the board back to the customer. There's a point at which the time/money spent on diagnosis and repair exceeds the value of the board, and this is WELL past that. I was hoping to follow through to the end, but I have a stack of other repairs growing. Thanks for the info guys!
  4. No shorts between traces, or vcc/gnd found yet. I did poke at the address and data lines with a logic probe. All data lines show activity. All address lines show activity, except A0, and A15-A19 are held low while powered. They are not shorted to ground though. Is that typical behavior?
  5. ROM has been swapped numerous times with known good. Contacts are clean. I can give this a shot. I haven't logic probed anything yet. This is my SE test rig. Analog is in great shape. Yup, 4 known good SIMMs installed.
  6. Update. All 6 RAM mux chips replaced. No change.
  7. My next hunch is the UI2-UJ4 mux chips. Anybody concur?
  8. I have an SE/30 board in for repair that I just cant figure out. It's been recapped, and corrosion was minimal. It shows the attached pattern. No chime, although I do hear 2 distinct "clicks" from the speaker at time of chime. All address and data line and other traces have been checked between ROM, RAM, VROM, VRAM, and UA8-UG8. Known good RAM/ROM/VROM has been swapped in. All UA8-UG8 chips have been replaced. Where would you go next on this one?
  9. It's worth noting that although the Toshiba 74HC166D is a CMOS part, it appears to be TTL tolerant. It worked fine as a replacement in my case.
  10. ISSUE RESOLVED! Techknight, you may want to add this to your notes. It appears that Texas Instruments SN74HC166DRG4 is NOT a valid replacement for the the 166 shift register @ UE8. It causes the discussed artifacts. I swapped it out again, but this time with a Toshiba 74HC166D, and the issue completely resolved!
  11. Also, I have tried swapping all 5 PALs with known good.
  12. Sorry to dig up a dead thread. Techknight, did you ever find anything on this? I have precisely the same video bug, but cant seem to figure it out. Both VRAM's and UE8 have been replaced. Tested all traces to and from VRAM. I still get vertical stripes with a slightly abnormal disk icon. Looks identical to your screenshot.
  13. I haven't looked at it close yet, but its not auto-injecting. I noticed one of the sensor LED's inside is glowing, so it is receiving power at very least. What were your symptoms?
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