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elemenoh

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  1. One error is that the PSU cap list should show 2x (not 1x) for #12 (3,300uF 10V). Another is a minor labeling error on the MLB. It's too late to edit the post, so new images for those below. I replaced 9,10,11,12,13, but the issue persists. The power-on pin shows 5V which goes low when the power button is pressed, but only a faint clicking from the PSU can be heard. Perhaps a bad transformer or transistor somewhere? Anyway, the nice thing about the clones is they use such generic parts. I ordered a new generic 20+4 pin PSU from eBay for $20 shipped which should fit perf
  2. I recently got a PowerBase 180 that won't power on. The MLB looks good, but I suspect the PSU needs a recap. Since info for clones isn't that common, I made a map of all the caps. There are a lot of them! Also, R2 and R3 on my PSU were quite crispy, but did test okay. They're 22kOhm 1% but not sure of the wattage in case you need to replace them but the color codes are worn off. I normally replace electrolytics with tantalums, but the 33uF tants are quite pricy. So I'm going to replace those with electrolytics.
  3. AFAIK those socketed chips are all proprietary. That sounds like an analog board issue to me, but someone else here can probably give you more specific advice. You didn't get that symptom with the SE logic board installed?
  4. This IIx logic board was not working after recap. I repaired a couple of obvious broken traces, but had trouble finding whatever was causing no signal to the PSU sense pin. I read a common problem is a break between R3 and R19, but it wasn't clear what side of either needed to be wired to the other. For others that might need a reference, here's the bodge that worked for me.
  5. That glitchy video may be due to issues with the video ICs south of the RAM. You might have more to clean or need to start swap testing them to isolate the issue. Someone else here might be able to give you more specific advice of which ICs to try, but generally start with those closest to the caps you replaced.
  6. I agree with @dochilli's advice. J12 might explain it and the socketed chips are an easy thing to try. Otherwise you're going to have to start methodically probing to hunt for broken traces. I might start with the ROM since you're not getting chime or video. It's also possible the board might be more cleaning. It looks clean in the photos, but it's possible some cap goo is underneath an IC causing problems. UE8 is a usual suspect for that kind of issue. If you get an ATX extension cable you can probe the logic board while it's out of the case which will make narrowing i
  7. What happens when you hit the reset button? Can you hear anything like the speaker crackling again?
  8. So your SE/30 logic board works okay with the SE analog board and your SE logic board works okay with the SE/30 analog board but not vice versa? If so, weird. What exactly happens when you have the SE/30 logic board paired with the SE/30 analog board? Does the fan run? What voltages are you getting? Have you tried disconnecting the HDD and floppy? Does that change anything?
  9. Is continuity broken when you do press? I can't recall if it's normally closed or open either. BTW, it looks like one of the clips that holds the RAM SIMMs down might be broken. Is that so?
  10. Oh and KiCAD wouldn’t let me use slashes in names hence the style inconsistency from the original.
  11. Wow thanks for doing that. A lot of these were due to the crumby scan and me not knowing the proper nomenclature to make a better guess. Very thankful to have the detail sorted out.
  12. Please share you’re notes about the errors you found and I’ll fix them. Quite a few issues were fixed after they were first published. How recently were you using them?
  13. Today I recapped a Color Classic (MLB and analog board). The machine booted prior to the recap, but there was definitely some leaking on the MLB and some video issues typical of leaked caps. After the MLB recap, the machine booted fine but the video issues remained. After the analog board recap, there was no power at all. No click/buzz when the switch was turned on and nothing when soft power was hit. All the caps were oriented correctly, no bridges etc. Then I noticed that when I was switching the power supply on a very tiny spark/arc on one side of the fuse. The fuse
  14. This is insanely great. Amazing work!
  15. Do you have some good photos of the board? Where was the rust? Perhaps some traces are broken to the RAM and/or ROM that are hard to detect. Have you already checked the traces to them with a multimeter?
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