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redruM69

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Everything posted by redruM69

  1. I've got a ROM 01 IIgs in that fails diags with error 03011500. From what I can decipher, it appears to be a state register failure, bit 01, address 15. Not really sure where to go from here though. My gut tells me CPU or maybe RAM. Suggestions?
  2. Oh well hey! Even better! I didn't know it was updated.
  3. @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
  4. 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!
  5. 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?
  6. 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.
  7. Update. All 6 RAM mux chips replaced. No change.
  8. My next hunch is the UI2-UJ4 mux chips. Anybody concur?
  9. 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?
  10. 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.
  11. 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!
  12. Also, I have tried swapping all 5 PALs with known good.
  13. 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.
  14. 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?
  15. Update: RESOLVED! I made an error/typo with my original assessment. It was column 3 the entire time. I wrote down the wrong value. This means I accidently replaced the wrong chip! It also appears the MB8264-20 is NOT compatible. I stuck in an NEC D4164D instead, and it worked fine. Replaced column 3 row E with another D4164D, and no more errors! Now to move onto the floppy drive not working!
  16. I recently acquired a Lisa 2/5 as a project. PSU fixed, corrosion repaired. It has 2x 512K RAM cards in it. Getting an error 70. I have narrowed it down to 1 card. The bad card is in slot MEM 1, MEM 2 left empty. Enter service mode, Read memory location $186 gives 0000 0000 0000 0004. Cool! From what I read, that means the chip at Row E, Column 20 is bad. Replaced the HM4864P-2 with a now socketed Fairchild MB8264-20, which I believe to be compatible. Still get error 70! Memory location $186 now gives 0000 0000 0000 0404 So it appears that not only did the RAM I replace stil
  17. Recapped an SE/30 yesterday. It still gives a simasimac screen, but with a GOOD boot chime, and a fast 4 chime with interrupt button. RAM has been swapped, ROM has been swapped. It had minimal cap corrosion with no PCB damage visible. No battery corrosion. Board has been thoroughly cleaned 3 times anyway. Ideas?
  18. Update on this project. I shipped it back to the customer and all was right as rain for a couple of weeks. It then reverted back to the same symptom! This board appears to be blowing opamps pretty quickly. I think we've come to the conclusion that its best we wait for another board to pop up, and swap it out. This one is just not reliable.
  19. Hmm.. Is it possible the Maxim is a more robust unit?
  20. It makes sense to me. If the opamp's output is way off, yet everything else checks out, then it must be toast. I did swap Q207 at the same time, but it tested good once I had it out of circuit. FYI, I replaced the original LT1179CS with a MAXIM unit. $10 a pair on eBay. Not sure what the original manufacturer was, but it was different. I appreciate your time. You were a huge help!
  21. Success! It appears the opamp swap DID work after all! Just for kicks I connected everything up, and performed a power manager reset. It booted fine, and reported the battery nearly full, and charging. With the machine booted, Pin 52 now measures 3.94v and climbing. Maybe bad op-amps are a little more common than previously thought?
  22. Difficult to find time to work on this one. That's the reason for the long delays in my response. Resistance between PMGR's pin 52 and ground and VCC is about 24meg.
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