Minecraft wiki entry for Clock, associated text: Using only redstone torches and wire, it is possible to create clocks as short as a 4-clock, sometimes by exploiting glitches. Using repeaters or pistons allows easy construction of any clock down to 1-clocks, and other devices can also be pressed into service. There are also special circuits called "rapid pulsers", which produce rapid pulses like a 1 tick clock, but inconsistently due to torches burning out. Indeed, torch based rapid pulses can be too fast for repeaters. Even with repeaters in use, 1-clock signals are difficult to handle in other circuits, as many components and circuits do not respond in a timely fashion.