Adding a reference wave
In order to duplicate an existing wave into a Reference wave, simply tap that wave’s indicator on the left of the screen, and select the ‘Ref’ option, as shown below:
Note: you can add as many reference waves as you want.
Adjusting a reference wave
Since the idea of a Reference wave is to keep it steady on the screen, it is not possible to scale its voltage nor time base. You can, however, freely adjust the vertical position of a Reference wave. To do this, simply drag the wave or its indicator.