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Fully recapped! Boot chime plays fine, but as soon as I try to play any sound from the control panel by selecting an alert sound, the system freezes. Initially, I thought this could be caused by new caps shorting to another line underneath, but it still freezes after even after removing the 3x...

Fixed!! Turns out it was a break from A(11) to the video rom. Not sure how but the board looked perfect around both areas

Actually, this can't be an issue with D(24) - D(31) right?

Traces from UE8 to V(0) - V(7) look fine. Both 41264 chips also have good traces to VCC and ground. Can anyone tell if this is an issue with UC6 or UC7 from the screens above?

Did a full recap and checked traces and it's still the same. Didn't think it was a caps issue. I suspect @finkmac is right and it's one of those 41264 chips. Going to try to replace them

The video is bad but other than that everything works! The board itself looks fine and I've swapped the video ROM with a known working se/30 with the same result.

It boots fine with a color classic board so confirmed the analog circuit is working. The original 575 board however doesn't power on, just nothing. Will the LC575 boot with a completely dead PRAM battery?

Yeah, it seems to be unlocked and I tried using the eject switch but nothing happens. Is there a 12V line from the power supply that I can check also?

Came across a duodock that looks to be in good shape from the board but won't take in any laptops, no clicking. Measured voltages across the power supply which seems fine with yellow wire being exactly 5V and blue wire at 21V Any idea why it won't take in a machine?

Adjusting the pot doesn't really work. I can get the 5V line up to 4.45V but it won't go any higher or the machine just starts clicking and won't boot. I think it might be because the 12V line is exceeding 12.3V? I'm guess I need to recap the analog board?

Reading around, there seems to be a pot that can adjust the 5v and 12v voltage. Need to give that a try

Yeah, strange right? It boings and boots to the floppy question mark screen just fine. The mouse works fine too

Pin 5 -12V, pins 7 and 8, are 12V Pin 6 5V only shows 4.3V, could that be an issue with the power board?

I recently got a Macintosh 128k that works and boots to the floppy and question mark screen, however Floppy Emu does not work on it. It shows the green light top left but oled screen is blank. Plugged in a known working floppy drive and it will not boot from it either, disk goes in and just...

Back to a working Portable! Thanks again @SuperSVGA @techknight @Byrd

Ahhh, that is the line that is under C14! It's connected but shorted to ground. I need to redo the soldering under that cap. Thank you so much!! How did you create schematics for the entire board, this is so cool and I've never seen one for the M5126 before :)

Oh, that makes sense! It just seems like so far from measuring the pins on the bottom row of the lcd connector J19, they all go to different pins on the video chip for me 🥴 Hmm, maybe it's not those then! I'll have to get some pictures but I can't find damages elsewhere on the board. Is it...

Fixed the keyboard issue. Turns out Y0 was shorted to ground causing the number "6" to always be pressed down and machine not turning on at all. Interesting that shorting shorting C116 to ground is like plugging in an external keyboard from J22 and that bypasses the internal keyboard circuit...

thank you!! Would you happen to have the video schematics by any chance?

me too please ;)