The “Y-Pos.” wheel determines the vertical image offset of both channels independently. In “Dual” mode i.e. two signals can be displayed in two different display areas of the screen without crossing each other.
The purple cable is attached to channel 1, the orange cable attached to channel 2. The “Dual” button is pressed. The “Y-Pos. I” wheel is slightly turned to the right (the signal of channel 1 is moved upwards on the screen), the “Y-Pos. II” wheel is turned to the left (the signal of channel 2 is moved downward on the screen).