Hi, got my hands on this and it will turn on, but no sound and nothing on the screen. 2 player (shoot & jump) and a blue button with a yellow "W" on it in the middle. (?) It has 2 PCBs tied to each other. Main connector : 2 player (Shoot and Jump) : Top PCB : Lower PCB : Power Supply : A tiny PCB connected to the main PCB : (?) Another tiny PCB connected to (?) with potentiometers : Its running with "Deutsche Mark" and had a "TÜV label dated 1991", so its probably older. Any idea ? Thanks in advance !