68kMLA Classic Interface
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| Macintosh LC schematic | |
| Posted by: amedeo_68k on 2023-03-14 06:55:47 Hello, I'm looking for Macintosh LC logic board schematic, not LC II / III / 475. Does anyone have it ? Thank you | |
| Posted by: joshc on 2023-03-14 07:53:05 LC should be very similar to LC II. @max1zzz might have something as he reverse engineered these. | |
| Posted by: amedeo_68k on 2023-03-14 08:42:34 yeah, it is similar but the components enumeration is totally different | |
Posted by: max1zzz on 2023-03-14 08:55:29MacLC-Reloaded/LC_Schematics-V1.1A.pdf at main · max234252/MacLC-Reloaded1:1 Reproduction of the Macintosh LC PCB. Contribute to max234252/MacLC-Reloaded development by creating an account on GitHub.
github.com
There are a few errors in that I need to fix, most notably i'm pretty sure the pins on the serial ports are connected in the wrong order but other than that it's should be 99.9% correct 🙂 there are also scans of the PCB an my traceing in sprint which may be useful for troubleshooting here: https://github.com/max234252/MacLC-Reloaded | |
| Posted by: amedeo_68k on 2023-03-14 09:12:10 Oh, thank you so much, so the +12V is required for audio to work (regulated to +8V) | |
| Posted by: LetsgetStarted on 2025-08-22 14:11:01 Old post I know.. Heads up.. Looks to me from inspecting an LC That capacitor C1 Positive(10UF 16V) connects to the UB10 Pin 5 directly... Not to R82 ,R83,C103.. This should be connected to UB10 Pin 5 and R83,C103 Please review! | |
| Posted by: max1zzz on 2025-08-22 15:55:49 Good spot! Positive on C10 should be connected to pin 6 on UB10 (along with R83 and C103) but not R82. I had it connected to the wrong side of R83/C103 (which connects to pin 5 and R82). Have corrected this 🙂 I will also say that the apple schematics are now floating around which should hopefully be error free | |
Posted by: LetsgetStarted on 2025-08-25 19:09:50Good spot! Positive on C10 should be connected to pin 6 on UB10 (along with R83 and C103) but not R82. I had it connected to the wrong side of R83/C103 (which connects to pin 5 and R82). Have corrected this 🙂I went on git hub and marked it as an issue about pin 6 yes I made a mistake not pin 5 ... old eyes lol.. Just used the schematic to trouble shoot and thought I had an open wire ! Had me going for a bit! | |
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