Redstone Repeater
A redstone repeater relays a signal in one direction, resets its strength back to 15, and adds an adjustable delay of 1 to 4 redstone ticks. It can also be locked to hold a signal frozen.
What does a repeater do?
A redstone repeater is a one-way valve for redstone signals. Power can only enter the back (the end with two locked-together torches) and leaves the front. It does three useful jobs at once: it boosts the signal back to full strength 15, it forces direction so power can't flow backwards (a diode), and it adds a delay you can tune.
Right-click (or tap) the repeater to step its delay through four settings, shown by sliding the front torch back. That makes the repeater the main tool for timing redstone.
How much delay does each setting add?
The repeater has four notches: 1, 2, 3, and 4 redstone ticks. One redstone tick equals 2 game ticks, or 0.1 seconds, so the delays run from 0.1s up to 0.4s. The default is 1 tick. Chaining repeaters lets you build up any delay you need — ten one-tick repeaters in a row give a full second of delay.
Can a repeater be a clock?
Yes. Feed a repeater's output back into its own input through some dust and it will oscillate, switching on and off on a steady beat. The longer the loop and the higher the delay settings, the slower the pulse. This is one of the most reliable ways to build an adjustable clock.
Key facts
- Signal flows one way only: in the back, out the front.
- Resets output to full strength
15regardless of how weak the input was (as long as it's above 0). - Adjustable delay of 1–4 redstone ticks (0.1s–0.4s).
- Powering a repeater from the side by another repeater or comparator locks it, freezing its current output.
- Acts as a diode — useful to stop signals flowing backward into a circuit.
Bedrock note: locking and 0-tick quirks
In Bedrock Edition a repeater is locked by powering it from the side with another repeater or a comparator, holding its output frozen until you unlock it — handy for memory cells. Bedrock also resolves repeater timing slightly differently from Java in edge cases involving simultaneous updates, so when a tight timing build behaves oddly, add a tick of delay rather than relying on a 0-tick trick. This simulator models the standard 1–4 tick behaviour.