Hi all,
I just replaced a broken octave slider (purchased from this site - thanks!), put it back together and now it doesn’t power up. I tried the AC adapter, batteries and USB. Screen doesn’t light up or even flicker, there’s no sound, nothing. I took it back apart and don’t see anything that I might have accidentally disconnected or could otherwise have screwed up.
Has anyone made a repair on this unit and have any ideas as to what I might have done or what I might try?
thank you!
John
Update: I discovered if I unplug the board that the octave slider is on, it powers up. Plug it back in, power goes off. I removed the new slider, but doesn’t change it. So something’s screwy on this board now. Any insights appreciated! Have a gig upcoming and a dead keyboard. 
Hey there, welcome to the forum.
You may have a solder bridge creating a short circuit on the board. A multimeter set to continuity testing can help you find where it is; it’s probably between some of the pads that the octave slider was soldered to. Once you find it you may need to clean up some of the solder with desoldering braid or sometimes a soft bristled toothbrush is enough to remove the bridge if it’s a very small one. Bridges aren’t always visible with the naked eye so the multimeter helps a lot if you have one. An ohmmeter works too but you will be looking for near 0 resistance between pads. If you have any questions feel free to ask.
