Akai X-201-D - Kurzschluß

Hello Hendrik,

The supply voltage for all electronic circuits is +23V.
This supply comes from the small power-supply board MR-503. Here you will find the power-transistor TR401/2SD223. It has 3 pins and I suggest you measure voltage on all 3 of them. One pin(the middle) will have around +30V and the 2 others around 23V. If one of the +23V is missing I suggest you replace the transistor. It's not important what you replace it with as long as the pin-out is the same and you think about minimum specifications (Watt, Vce, Ic, NPN-type etc). Sanken, the original manufacturer, suggest you replace it with 2SC3179, 2SC3851.
Here are the specifications for 2SC3179:
http://www.sanken-ele.co.jp/en/prod/semicon/pdf/2sc3179e.pdf

If you need the schematic diagram PM me with your e-mail address.

good luck


mfg,

/tri-comp