Minecraft wiki entry for Redstone_Repeater, associated text: A repeater's delay can be modified by using the Use Item control. Each use increases the repeater's delay by one redstone tick, to a maximum of four redstone ticks, then back to one redstone tick. Longer delays can be made with multiple repeaters – for example, a repeater set to 'four' and another to 'one' provides a half-second delay (0.4s + 0.1s = 0.5s).