Hello friends, I have a microkorg-s, which has speakers included, it is a re-edition of the classic MK1 and they have modified the internal PSU, now it is no longer as it is in the schematic and I can’t find any information. Has anyone been able to repair one like this before? thank you.
There’s a high number of similar issues online. All seem to point to a power adapter supplying more than 10V frying a 3.3V regulator.
you have two issues to solve, investigate the power adapter and then solve which regulator has failed.
However if this is a later model then this may have been addressed and there is another reason for failure.
Either way start with testing the power supply to see if its putting out the correct power. Then verify the power plus is the right orientation for the synth, (center positive, barrel negative or reversed) Then see if the mainboard regulators are working.
Surface mount electrolytic caps have a high failure rate so there’s a possibility some of them have failed too, they usually give off a fish smell if leaking.
Hello, the 5v voltage regulator outputs 5v, the 3.3v outputs 3.3v, the reset outputs 3v, all the regulators are good, I’m thinking that it could be the problem of the TDA and TPA that there are, because everything that I have measured it is fine…
i’ve repaired a couple of non-booting ones plus others behaving strangely in the past
at a time i even redid the power supply on a very early model since those where poorly designed
if you still have trouble feel free to ask
given your unit doesnt turn on I would advice you on checking the fuse right after the main power rail
that one fails when the cpu shorts (very common)
i’d say that’s what’s most likely for you since you say the voltages are okay i’d bet the fuse is blown and the cpu is shorted
if so it isn’t as bad as it sounds — you need nothing very fancy to replace that plus i know of good sources for that and any other component plus i have some i would ebay