Circuit Library

This project sets up two flashing LEDs, one red and one blue, to create a police lights effect. You can use this circuit to integrate into a toy, or just to practice your circuit building skills. The circuit is built around a [555 timer](https://www.build-electronic-circuits.com/555-timer/) in astable mode.

This circuit creates a light that "runs" back and forth using a 555 timer and a decade counter. It's effect is similar to the light bar on the car from the old television show Knight Rider. It's a really fun circuit to build. I once built a larger version of this for the inside of a party bus when I was a teenager. Unfortunately, I broke it the first day because I increased the voltage too much! But that's another story...

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](https://youtu.be/wSN8_ChDztw) to hear the circuit in action.

Here's how to build a simple LED blinker using a 555 timer. The 555 timer is configured as an astable multivibrator, which means the output will turn on and off repeatedly. With the chosen values, it will turn on and off about five times per second. Since the LED is connected to the output, it blinks =)