Good day/evening everyone, I'd like to know if there are any problematic cases for such MIDI synths? Mine came from Japanese auction and was sold "untested", therefore I had high hopes I'd get a working unit (naive from my side, as it seems), later on I discovered that it doesn't power on. Tried with SUM-1 (D sized) batteries for now, as was suggested in the manual, therefore I also thought of trying with AC Power Adapter (9v), but would it be worth trying? As of now I have it on my table, de-soldered ground wire to get further, in order to check both PCB's for any problems, however I cannot recall any problems, as visually they seem alright. Sadly I do not have voltmeter with me as of now and I can't really say that I'm experienced in electronics, help would be appreciated, thank you in advance!
(I tried to follow this video below, they state that usually the problem is with the T3 Diode and Capacitor)
https://www.youtube.com/watch?v=26cBDE9Ac4I