68kMLA Classic Interface

This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.

Click here to select a new forum.
SE/30 with SimasiMac - vertical stripes with floppy icon
Posted by: anmwinter on 2022-10-09 11:40:03
Afternoon all,

I came across a SE/30 of unknown status. Digging around on the forums here and watching Branchus Creations on youtube lead me to cracking the case open. The PRAM battery was intact but the caps were leaking or had leaked. I did a cleaned up and recapped the board with tantalums. Using fancy words here but all I really know about soldering and reading diagrams is from working on my '87 4Runner.

I cleaned the board in IPA and then did a soak in sink with soapy water. Rinse, dried, and cleaned again with IPA.

I am not a computer wiring type person so this is all a bit new. I have some fond memories of dad working on his SE/30 with that glow spilling into the other room. My sis and I would be allowed on it to play Scarab of Ra, Dark Castle, and Cap'n Magneto. Mostly this project is to get one up and running again so my sis and I can play some games we never finished (life interrupted).

PXL_20221009_155254937.jpg
Posted by: anmwinter on 2022-10-09 11:42:48
Things I noticed is that the UE8 chip(?) has some corrosion on the side facing C7. Near C7 left hand side there was a spot of corrosion on what I think is a trace (fatter line)? I cleaned that up.

I get the attached pic which from this thread https://68kmla.org/bb/index.php?threads/mac-se-30-with-strange-simasimac-help-needed.1069/ kinda points the way? I don't really understand what "Connecting the A0 address line between UD8 and UK6" means.
Posted by: anmwinter on 2022-10-09 11:44:43
I am guessing at a minimum the UE8 needs to come out and be replaced? I am not sure how to do that. I figured out the caps single it's just a single point of contact in two places.

Oh I did cleaned up the cap pads with the flux, new solder, wick, and repeat til clean (from Branchus). Still no idea why that works.
Posted by: ymk on 2022-10-09 11:47:19
Jail bars every eight pixels is typically one of the UE8 data lines.

Looks like you restored continuity to one of them.
Posted by: anmwinter on 2022-10-09 11:47:48
The SE/30 did come with Radius pivot V1.4 card which I pulled out. It was in the way. And I don't have an external monitor.


PXL_20221009_155254937.jpg
Posted by: anmwinter on 2022-10-09 11:48:53
@ymk Thanks! That is helpful. So I should keep working the problem in that area?
Posted by: anmwinter on 2022-10-09 11:53:04
Oh not really related I pulled the floppy, partially disassembled it to remove all the dust bunnies. Cleaned off the old grease on the drive (saw in another youtube video) and regreased it.

Even with the funky screen I put in a floppy and it's ejects nicely! So kind of a win.

It also has a IBM WDS-l80, 80mb hard drive. I pulled that too look at it. Apparently the LED cable won't connect nicely to the HD pins. It was disconnected when I opened it up.
Posted by: anmwinter on 2022-10-09 11:58:59
No startup noise but occasionally some weird sound through the speakers. I'll see if I can get a recording of it.
Posted by: anmwinter on 2022-10-09 13:21:20
Looks like it's a heat gun with fancy nozzle to remove those chips. I poked around on the forums here and found the parts # for those chips (video muxes?) and got those ordered today. I'll lift those off and see what's going on under them.
Posted by: ymk on 2022-10-10 17:30:49
@ymk Thanks! That is helpful. So I should keep working the problem in that area?

If the picture is fixed, it seems you've sorted it.

Those data lines might be dodgy at another point, but typically it's UE8 that gets cap crud on it.
Posted by: anmwinter on 2022-10-17 07:57:46
I just got the new chip in the mail. So I will desolder the old chip, do a clean up, and drop in the new one. I'll let ya know what happens. I suspect there are other things I need to fix as well 🤣
Posted by: wottle on 2023-02-13 14:22:00
I have an SE/30 that is doing this as well. Did replacing the chip solve the issue?
Posted by: chrisdaun on 2023-02-13 15:26:46
Curious to see if that fixes it as well.

My SE/30 currently wont boot past the cursor, and no chime when booting.
I replaced all the leaky caps and toned everything out with a multi-meter in continuity mode.
I couldn't find any broken traces but there was some corrosion on the UD12 and UI12
Posted by: chrisdaun on 2023-02-13 15:27:48
IMG_2353.jpeg
Posted by: Fred1212 on 2023-04-01 20:57:02
Did you fix this?
Posted by: wottle on 2023-04-03 07:47:38
For mine, replacing UE8 fixed the jail bar patterns. Upon closer inspection of my board, I noticed corrosion on some of the pins for UE8, and as I was doing some aggressive cleaning, the pins broke off. I used this as a replacement: https://www.digikey.com/en/products/detail/texas-instruments/SN74LS166AD/1590375

After the new chip was installed, my video signal was bar-free.
Posted by: Fred1212 on 2023-04-07 19:48:43
Thanks for your reply. I've replaced UE8 and still get vertical jailbars and only clicks and pops from Speaker. Have ultrasonic cleaned and recapped. It's progress as started with black screen. Cheers
Posted by: mg.man on 2023-04-08 01:50:00
I've replaced UE8 and still get vertical jailbars
Sorry, haven't read the whole thread... have you buzzed out all the connections in / out of UE8 & the VRAM? If not, I'd start there. Also, FWIW, I've killed an otherwise intermittently working SE/30 'board by US cleaning - so it's hardly a cure-all. Buzz it out if you've not already.
Posted by: Fred1212 on 2023-04-13 20:49:59
Thanks for your replay. yes have checked all address and data lines.
1