555 Machine Gun

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This "machine gun" circuit generates a sound that mimics the sound of a toy machine gun. It is based around a 555 timer IC in a feedback loop.

Check out this demo video to hear the circuit in action.

555 Machine Gun Schematic

The 555 timer is set up in astable mode, although not the "normal" way, but using a feedback loop from the output. It generates a continuous stream of rectangular pulses. These pulses are shaped to create a rhythmic sound that resembles a machine gun firing.

555 Machine Gun Parts List

R1
100k
C4
100µF
C1
10nF
C2,C3
10µF
R2
47k
U1
555 Timer
Speaker
8-ohm
Battery
9V
Q1
BC557

How to Build the 555 Machine Gun

Make sure that all the electrolytic capacitors and the transistor are connected with the correct orientation. Here’s how you can build the 555 timer machine gun circuit on a breadboard:

Make it your own

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