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.
Color Classic display issue
Posted by: dan75th on 2025-09-19 18:45:14 View attachment IMG_7574.mov I have a Color Classic that was recapped before I bought it, and I swapped the board with an LC550, which I just recently recapped as well. Since I got it, it’s had this weird issue with the display where it kind of pulses or waves most of the time. It’s easiest to see along the edges, but it affects the whole picture. I tried to capture it the best that I could in the attached videos. I just replaced the most common leaky caps on the analog board (the ones listed here: https://recapamac.com.au/macintosh-cc-analog/ ), but unfortunately it did not fix the wavy display. Is there a CRT adjustment that I’m overlooking somewhere? Is there another capacitor or set of capacitors that I should replace? What could be causing this issue? Any help is greatly appreciated. View attachment IMG_7573.mov
Posted by: ArjenCNX on 2025-10-14 00:08:14 maybe magnetic interference ?, could there be a source of magnetic fields nearby? also cracks in PCB traces are not uncommon, and neither is soldering issues, at the least re solder all transformers back down to the board, every pin needs re-soldering. also carefully listen for arcs, especially from the flyback transformer, sometimes there is internal arcing that can cause these things
1