68kMLA Classic Interface

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Fine vertical line on 128k
Posted by: macfan2350 on 2020-01-24 12:29:23 Hey guys, hope your doing well. I wanted to ask another favor of you guys. A while ago, I had asked about my mac 128 with a fine vertical line issue. You guys asked me to reflow the solder, which I have done. However, the problem still persists, and I wanted to ask if you had any ideas. I get no beep. just a fine vertical line. Sorry for not getting back after over 4 years. Thanks again. I really appreciate it. See attached photos: View attachment 10974 View attachment 10979 View attachment 10981
Posted by: Crutch on 2020-01-24 13:32:21 Did this 128k ever work? The bright vertical line sounds like an issue with the analog board driving the CRT (having reflowed J1, check the Dead Mac Scrolls, pp. 46-48, for similar problems and their solutions ... however all of these assume you get a bong) but no bong sounds like the 68000 can’t see the ROM. I wonder if you might have two different issues with this 128k. Is the logic board getting 5v from the analog board? (check voltages on the rear floppy connector.) Someone else probably has a better idea, I haven’t worked much on 128k issues.
Posted by: macfan2350 on 2020-01-24 14:28:31 Hey! Thanks for the reply! I managed to get this thing to show picture by patching a corroded trace on the analog board. However, I now face a new issue. it turns on and gives me a checkerboard pattern. I look at the logic board and find that the Roms are missing. Guess I'm stuck until i find new ones. Thanks again for the reply.
Posted by: Crutch on 2020-01-24 14:44:55 Oh yeah, having no ROMs at all would be one more thing that might prevent the 68000 from seeing any ROM ... 😉 glad you found the issue!
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