Roland SC-88 Pro

A while ago, like months at least, Speedy posted that she had a dead SC-88 Pro that she was looking to pass along. I want to say this was either just before or right after I got my SC-55 MkII so, not really thinking I'd want anything else for the time being, I passed up on it.

Last month or so, Speedy mentioned again that she still had the dead SC-88 Pro. This was just after I got my SC-55K, FB-01, and EMT-1. Knowing that I'm now interested in it, and wanting to see it live again, I said I'd take her up on it. $50 and a little while later, it's here.

Here it is! Neat-looking front panel, it's like my SC-55 mkII but busier and bigger. Is pleasant the word to use? Let's go with that.

No screws in the side of the case? Eh, whatever. She did say it's dead so hey, easy disassembly!

Huh, I think that top board is misaligned... the back isn't currently too pretty but whatever, that's fine.

Easy enough to get things back in place, just remove the one screw holding whatever this top board is to the chassis then reposition said board so it's in the right place. Phew. I was worried for a second.

Speaking of "whatever this top board is", check that thing out! I see what looks like RAM, ROM, some Hitachi microcontroller, and a CR2032 in a holder. Neat stuff! The connectors and wires on the bottom are a little messy but whatever, it's fine.

Here's the stuff below that top board. I see a power switch, fat transformer, power output board, and all sorts of random stuff with capacitors. I assume the analog portion of the board? It only makes sense 'cause it looks like the analog part of a Zaxxon PCB!

Here's also where my first point of focus is gonna be. Speedy told me that the thing just doesn't power on so I can only assume something on the mains, the output, or the transformer itself has to be dead...

Here's a better look at the whole power portion of this. We have the mains going into a board, a switch blocking it from going anywhere until pressed, then it goes out into the transformer. Neat multi-voltage transformer. Power comes out and by the looks of things we have we have a few differnt voltage lines. Oh boy. Also, see those (probably) filtering caps to the right of the power output board? Good gosh that glue below 'em looks horrible. Wonder if the things leaked? I'll have to test them out.

Not much googling later, I found a service manual. I uh... so we need 5V and 12V. Makes sense.

I took a multimeter to the outputs and, from "top to bottom" on the previous picture showing the output board, I get the following voltages:

Sooo... heey... about that 12V...

I guess I'm gonna need a new transformer. Speedy linked me one that's of a similar series to what Flyingharuka used to revive a SC-88 with an entirely missing transformer, thing is I can't seem to find one on aliexpress with the same voltage outputs? I guess I'll have to dig around a while.

Break until I buy a new transformer 'cause this one isn't working right.

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