REDSTONEPEDIA › Circuits › Pulse shapers

Pulse shapers

Turn a lever, a button or an observer's flicker into exactly the pulse a machine needs: one short pulse when a lever is flipped (fire a dispenser once), a long press cut short, or a 1-tick blip stretched so a piston notices it.

Filter them in the index

The pictures show each design with its inputs and a lamp on its output; the block counts leave those out.

One pulse on every switch (dual-edge detector)

A short output pulse every time the input changes, on or off.

2-tick pulseOne pulse on every switch
2- to 40-tick pulse · 2 to 29 blocks
pictured, 2 ticks (0.1 s): starts after 2 ticks (0.1 s) · needs an input of at least 2 ticks (0.1 s) · made of observer, redstone lamp · fits in 1×1×2
12 versionstiles side by sidelies flat (1 block high)

One pulse when switched off (falling-edge detector)

When the input turns off, the output gives one short pulse; nothing when it turns on.

2-tick pulseOne pulse when switched off
1- to 256-tick pulse · 2 to 24 blocks
pictured, 2 ticks (0.1 s): starts after 4 ticks (0.2 s) · needs an input of at least 6 ticks (0.3 s) · made of observer, sticky piston · fits in 1×1×3
23 versionstiles every 2 blocks1 block wide

Signal stretcher (pulse extender)

A short input pulse comes out at least a set length long.

at least 4 ticks (0.2 s)Signal stretcher
stretches pulses to 4⁠–⁠256 ticks, by version · 2 to 24 blocks
pictured, 4 ticks (0.2 s): starts after 4 ticks (0.2 s) · needs an input of at least 2 ticks (0.1 s) · made of repeater · fits in 1×2×1
21 versionstiles side by side1 block wide

Signal shortener (pulse limiter)

The output pulse is cut to a set length, however long the input stays on.

at most 2 ticks (0.1 s)Signal shortener
cuts pulses to 2⁠–⁠511 ticks, by version · 2 to 17 blocks
pictured, 2 ticks (0.1 s): starts after 4 ticks (0.2 s) · needs an input of at least 6 ticks (0.3 s) · made of observer, sticky piston · fits in 1×3×1
24 versionsalso the best “one pulse when switched on”tiles every 2 blocks1 block wide

One pulse when switched on (rising-edge detector)

When the input turns on, the output gives one short pulse; nothing when it turns off.

4-tick pulseOne pulse when switched on
2- to 256-tick pulse · 2 to 24 blocks
pictured, 4 ticks (0.2 s): starts after 8 ticks (0.4 s) · needs an input of at least 4 ticks (0.2 s) · made of observer, repeater, sticky piston · fits in 3×2×2
22 versions

A card that comes in several sizes lists every size, with the best design of each, on its page.