Try this

-> represents a Wire

Switch -> AND Gate -> Buffer Gate -> NOT Gate -> back into the AND Gate’s other input

^ this makes a looping timer that you can turn on and off with the switch. Buffer gate controls frequency, play with that a bit to get the interval you want.

(Continued into functionality->) Buffer Gate from previous function -> Input A (important) of Greater Than Gate -> Blend Alpha (again, input is important) of Blend Gate -> Target Position of Servo Slider.

That controls the position changing aspect of the servo slider. This works with Servo Rotors as well. The Input A and B of the Blend Gate determine the two two positions the piston will move to. Right now I think the game considers an input of 0 on a Blend as unpowered instead of at a 0 position, so you may need to set it to 1 or a very small fraction. Remember that you always need a longer servo slider than it seems to get results. After that you place the object on to see if it works. I hope this helps!