So, Im not sure if this has been done before, but i was working on a slime based bouncy house in my realm and needed an on/off switch for my repeating redstone clock and while i cant remember why the space constraints required adding an observer in originally when i add a switch to the mix i got this. When the lever powers the redstone the signal stops repeating because there is no change for the observer to detect. When you turn it off the dying signal gets carried the observer detects the change and repeats it causing the redstone clock to repeat. Now, if this has been done before that's fine, I'm not wishing to take credit. I just know I dont see redstone clocks like this used very often and was excited to share since I didnt get it from a tutorial but accidentally discovered it. Pretty sure this could be otherwise used for other things needing repeating signals.