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SE/30 Motherboard Repairs?
Posted by: Turaiel on 2022-05-15 11:17:53
Hey folks,

I've got an SE/30 that I started working on a few years back. I got all the caps replaced but I wasn't able to get the floppy drives (internal or external) working, despite cleaning and lubrication. At some point I made a mistake while probing for voltages and accidentally shorted a data line to a power line on the floppy connector. Ever since then, the floppy drives aren't recognized at all and when I try to restart or shut down, the machine unrecoverably bombs with a "bus error".

I'm not very experienced with diagnosing electronics problems, so I was hoping I could get some suggestions on things to check for. I'm really hoping I didn't toast the SWIM because getting a replacement without sacrificing my other SE might be a challenge. Also, if anyone has ideas or links to documents for how to fix the floppy drives, or suggestions for other things to fix up while I'm in there, I'd appreciate that as well.

Thanks!

Posted by: ironborn65 on 2022-05-15 12:51:43
Hi,
the SWIM is probably toasted, I'd try replacing the drive with a known working one before attempting to replace the SWIM.
Sorry I can not help more

PF
Posted by: Turaiel on 2022-05-22 12:29:59
Shoot, that's a shame. I tried two known-good 800K drives on the external port and they both failed to operate on my SE/30 but worked on my SE. The SCSI connection for the hard drive (in this case a SCSI2SD does work. Looks like swapping the SWIM also isn't an option because the SE (which would be my donor) doesn't have a SWIM; just an IWM.

Any other ideas?
Posted by: ironborn65 on 2022-05-24 07:49:11
nope, sorry to. give bad news, at least it:s my opinion
Until you find a SWIM you can "happily" live with the SCSI
Posted by: pocketscience on 2022-05-24 15:26:36
Also, if anyone has ideas or links to documents for how to fix the floppy drives, or suggestions for other things to fix up while I'm in there, I'd appreciate that as well.
These helped me restore a few old drives with great success: https://www.youtube.com/c/JDW11/search?query=floppy
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