Minecraft wiki entry for Pulse, associated text: This observer pulse edge detector is one of the most common edge detectors due to its modifyablity. It can be oriented in almost any direction, and the observer can be oriented in almost any direction, allowing for lots of flexibilty. And depending on where the output is taken from, it can be a rising or falling edge pulse generator. The observer can also be updated by other circiutry to send more pulses from the output.