Hi all

I thought I'd share a simple fault, diagnosis and repair tonight.

My Roland SC-88 (Japanese import converted to 240V) is split between being used by DOSBOX on my modern PC and my Roland keyboard. (MT-32 and SC-55 are on the PII PC with Keropi's ISA MPU CARD but that's another story) Halfway through some piano practice, it cut out, made a horrible static hissy sound and cut out. The display still worked and registered input so it wasn't totally dead.

I opened it up, removed the top (digital) board and inspected the lower (analogue) board suspecting an audio fault. I couldn't see anything obviously wrong there so proceeded to inspect the top board. Sure enough, all but one of the six SMD capacitors had gone bad and barfed their electrolyte all over the surrounding board. The worst offender being the largest 100uF cap which smooths the incoming power.

I removed all six caps. Definitely leaked electrolyte which had to be cleaned up. Smelled like rotten fish when desoldering. Cleaned up with IPA, checked for obvious damage and tested continuity. Can you spot my trace repairs? Solder blobs by C38 to reconnect the vias to the traces and silvered traces where I’ve removed bad solder mask and soldered to strengthen corroded traces.

Caps are in. I’m went for through hole Rubycon (very good brand) caps as replacements rather than smd ones.

I replaced 1x 100uF 16V and 5x 10uF 16V capacitors with the same value but rated instead at 25V in the hope they last a bit longer. 16V should have been fine but meh...

Spot the most useful mod.

Plugged in, powered on and all back to life! Phew. Hope this helps others.