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I'm replacing some SIMM connectors with broken plastic clips with new metal-clip connectors on some SE/30 boards. The solder on the data pins was easy enough to get out with solder wick. But the ground pins are being unsurprisingly difficult. I've tried lots of flux, adding fresh solder and...

I just ordered a set of caps to service several Color Classic analog boards. There are 23 different caps on this board, so just getting all the right stuff in the cart was tedious. Here's a Digikey cart link to make it quick and easy for anyone else doing the same...

@bibilitThat did the trick! It's working great now. Thanks!

Not many areas flaked off. I think I've now checked every trace and did find one bad connection. Patched that but got the same symptom. All the joints were reflowed anyway. Even with a lot of flux and scrubbing the pins on the IC don't look great, but test okay. I guess I can try swapping...

After a full recap of the PSU and daughter board, the Mac won't power up. When I swapped the daughter board from another working (recapped) PSU it worked okay. So something is bad on this board, but I'm not sure what. I gave it a couple of cleans and checked that all the pins make contact with...

Updated the RAM SIMM page with a couple of minor labeling corrections.

This one is pretty interesting. It boots with a typical samasimac screen, but the chimes are all over the place. I guess I have an accidentally circuit-bent SE/30 synthesizer! I've already replaced UD8, UE8 and UF8. Known-working ROM and RAM is installed. This is a different board than the...

I triple checked and booted with another board OK. Moved its ROM and RAM to this board but get the same result. Slow chimes. Does replacing the F258's next make sense?

I checked all of the data lines and did another inspection for solder blobs but didn't find anything wrong. After shuffling the socketed chips again it now gets a slow chime with samisimac pattern. All ram socket pins tested okay. So maybe I have one or more dead F258s? I ordered some from...

OK I finished fussing with the address lines and the KiCAD files have been cleaned up, archived and added to the shared folder. The topmost sheet just links to the other sheets at the moment. I didn't import any of the global pins onto it, but that should be quick and easy if it's helpful to...

Yep I did try with a known good stock ROM too but got the same result. 

I'm going through everything again and creating bus lines for address lines and other grouped, but not connected things. This should help with readability and linking between sheets. I've got a couple done already and should have the others done in a few days.

@Bolle  The original symptom was no chime or video. I got video after replacing UF8 and UG8. Now I get no chime and just a static samasimac screen . A broken connection for A11 was patched, but the symptom did not change. I checked all the address lines again and couldn't find any other...

@blindowlThanks for pointing that out. It's fixed!

I've corrected a couple labeling errors and added a cheat sheet at the end showing all the pins for each component connecting to each address line. Let me know if you have ideas about how to better arrange it.

I ended up adding them all. Still open to feedback about them though.

I've added some pin maps to the first page. Let me know if these are good or if the style needs tweaking. If they're good, I'll add them to the rest of the pages.

I have no EE background and couldn't read a schematic a couple months ago let alone make one. I don't think I want to deal with the learning curve to make a layout for the PCB. My goal was to copy the Apple schematics as closely as possible so that they'd be easier to read during...

@marcelv Thanks for the cheat sheet. I tested all of these again including their respective address lines at ROM, GLUE, VIA, SWIM Serial and Sound. All checked out okay. Last night I did the same for UA8 and UB8.  I did just find that A11 was broken at UI3. I patched that but still get...

I replaced UF8 and UG8 and now get video! It's simasimac, so still more troubleshooting to go, but making progress. Thanks @Bolle!! BTW if it's helpful for others, I'm getting the following values at J12 after replacing those binary counters: Pin 10 (HSYNC): 22.24Hz / 2.7V Pin 11 (VSYNC)...