I am working on an Emulator I that has some burnt components on the right side control board. Does anyone know what may have caused this? 1i checked the power supply and all voltages seem to be within specs.
Shorted tantalum cap. Replace all with electrolytics.
Are those the caps on the ps board?
Those blue components on the control board are tantalum caps. The big problem with tantalums is their failure mode is a short. So when they eventually go bad the results can be catastrophic, as you have there-an exploded cap.
The PSU may also have tantalums, but guaranteed it has one or more larger electrolytic caps. These also should be replaced for future proofing. I would address the blown up tantalum cap first by replacing it with an equivalent electrolytic along with every other tantalum cap in the unit.
I ordered all new caps for the psu and caps to repalace the burnt ones on the control board (all electrolytic). I also ordered new voltage regulators. When I turned the unit on the first time the caps on the control board started smoking within a few seconds so Im thinking one of the voltage regulators failed and sent 19v to the control board. I am going to install the new components tonight. I thought about replacing the transformers but they seem to work. My main concern is what else could have been damaged due to overvoltage. I agree with changing all the t-caps with electrolytics.
Are there any other components I should check before powering this thing on again? I am a computer tech and have zero experience working on synthesizers so I really appreciate your help. Thank you!
If possible I would disconnect every PCB from the PSU and, using your DVM, verify that each one is not shorted across its power connectors. If they all seem okay then reconnect the power to each board and do the smoke test.
I replaced the bad caps, double checked the voltages and everything is within specs but it is still having an issue. All the switches and leds work and bootup seems normal. All lights come on for a few seconds then shut off and it reads lower and upper disk but has no sound output. Any ideas what could cause this? Maybe a bad IC or sound profile on disk is missing or corrupted.
Get yourself one of these $30 IC testers on ebay and go through the entire machine.