PC-ENGINE DUO-R the river cable does'nt fit in my plug!?

[RichterBelmontxX]

Hello, I have a Japanese Pc-Engine Duo-R, I am from Germany, and the river cable does'nt fit in my plug! Must I use a Adapter or so?? If yes, which?? Or what I must do, to play Pc-Engine without problems??? Please helpt me!

[guyjin]

I'm not sure what you mean by "river cable". Please explain.