| Click here to select a new forum. |
| Mac Plus not starting |
Posted by: theminidriver on 2021-12-11 03:49:43
Trying to boot up my old Mac Plus after 25 years. Anyone know why it sounds like a pool cleaner 🙂
No display on screen either, not even the sad Mac 🙁 |
Posted by: dochilli on 2021-12-11 04:49:05
Could be a defect Q2 (BU 406).
Did you check the voltages at the floppy port? Should be 5 and 12 V. |
Posted by: theminidriver on 2021-12-12 04:28:10
I got my hands on a copy of "Macintosh repair and upgrade secrets" now. According to that, it seems like the power is automatically cutting out and restarting through the over voltage protection circuit. I'm going to try get all the recommended replacement parts for that.
But when I took off the protection jacket on the analog board, I saw what looks like a massive modification. Anyone know what the purpose of this might have been? There are also some strange mods the other side too. |
Posted by: theminidriver on 2021-12-12 06:52:58
Looking closer, it looks like 2 more caps were added, more like the International analog board setup. |
| 1 |