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.
Macintosh SE Display Issue
Posted by: xilmwa on 2016-01-14 20:44:33
I'm mostly on the PowerPC side of the fence, but I got ahold of a Macintosh SE (it's actually an SE with an SE/30 logic board). Since I've got it, though, I've had display issues like in the attached image. From what I can tell, the CRT is duplicating the image and shifting it down a few pixels, rendering the image unreadable. Also, the picture changes size subtly.

I have checked the logic board, and didn't see any major signs of corrosion, so my best guess is that the capacitors on the analog board have gone bad. Am I on the right track?

IMG_2016-01-14 22:40:26.jpg

Posted by: Elfen on 2016-01-14 22:16:36
That is a problem with one of the ICs around UE8 having a bad trace going to it. Uniserver would know exactly which one it is. That area controls the video for the Mac.

Posted by: xilmwa on 2016-01-15 09:53:28
I may have goofed, but I ran over the line of ICs around UE8 with vinegar first then isopropyl alcohol second, then dried with a paper towel. I now get this; is this what's called SimasiMac? Does the diagonal refresh line mean anything?

Also, I should note this isn't the first time it's done this. I was actually quite surprised it chimed at all last night. 

IMG_2016-01-15 11:52:18.jpg

Posted by: xilmwa on 2016-01-15 11:08:12
Looked through old posts and saw another mac with the same pattern; Simasimac then. Any suggestions for who to give the job?

Posted by: Instow on 2016-01-15 13:29:43
Contact Uniserver, he will be able to give you an idea of what the problem is, and the remedy/cost - probably a board re-cap.

Search for him on this forum, or www.maccaps.com.

He's fixed boards for me, and many others here, I have a Simasimac SE30 board going to him next week.

Posted by: Macdrone on 2016-01-15 13:43:33
If its a SE/30 board you need a board clean and capacitor recap as stated and Uniserver will look for any bad traces.

Posted by: uniserver on 2016-01-15 13:44:07
yup you are correct the caps on the main board have gone bad.

Posted by: techknight on 2016-01-15 14:13:13
Yea, I was going to ask, has it even been recapped? 

1