68kMLA Classic Interface
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| Click here to select a new forum. | | Classic II with checkerboard screen | Posted by: AndyO on 2021-10-17 13:44:11
I have a Classic II which has booted in the recent past, but has sat unused for many months. When I go to boot it up, I get a checkerboard screen (large black and grey squares like a chess board), and then at the next attempt, thick black and grey vertical stripes. I can hear the fan running, and the drive spins up.
I'm fairly sure I've seen posts about these symptoms, but I can't find them in a search, so I was wondering if there's a common cause for this behavior.
The system has not been recapped - indeed it hasn't had any work done on it at all that I know of, but I have only had it about a year. When I got it, it booted and worked, though not reliably. Sometimes it would simply hang up as it started. It was really cheap so I didn't actually expect it to work at all!
I don't have the skills necessary to repair it, or even recap it, but I'm curious what might be the obvious cause(s) of this - at least then I may have some idea which bits to mail off somewhere to have fixed! | Posted by: joshc on 2021-10-17 13:54:09
Yep, bad capacitors on the logic board are the most likely cause of that. From my experience, the caps leak pretty badly on them.
The analog board should also be recapped if it hasn't been already. | Posted by: AndyO on 2021-10-17 14:36:25
It hasn't, and to be honest I doubt it has had any work on it at all, ever. I will likely need some expert help! | Posted by: dochilli on 2021-10-18 00:27:31
Sometimes cleaning the Logicboard with IPA can solve the checkerboard problem. But you have to recap the LB and the AB as soon as possible. There can be a lot of problems if you wait to long. And the battery should be removed!
There are tutorials on youtube for recapping macs:
There are different techniques to remove the old caps. I use the press and twist technique, in the video hot air is used.
The videos of JDW are also very good:
| Posted by: AndyO on 2021-10-18 05:31:21
I don't have the ability to do a recap myself - I'd be happy to try, but don't have steady enough hands unfortunately to do anything more than a very bodged soldering attempt. I am happy to disassemble the computer to send the boards off for recapping though!
It is possible it has battery damage - though it did work reasonably well until recently. However, I haven't taken the back off yet to find out.
I suspect I'll be a customer of Amiga of Rochester before long! | | 1 |
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