Question about Max Hauri Digital timer, random generator

I don't see any S. Do you mean R?
The instructions are poor and there are some difficulties. E.g. a Random button that causes random on and off. In random mode, a small R (light in a black box) appears on the display (centre right). This is easily overlooked. Press the Random key again to switch this off. If you have programmed switch-on and switch-off times, you can switch on or off manually with the on/auto/off button. If the status is on and is changed to auto, the clock remains on until the programmed switch-off time is reached. On auto, the clock does not have to be off until the programmed switch-on time is reached. The reverse is true if you change from off to auto. This gives some possibilities but also error possibilities.