A Simple 555 PWM Circuit with Motor Example

In this tutorial, you’ll learn how to build a 555 PWM Circuit. You’ll modify the standard astable circuit with a couple of diodes. And you’ll see how you can use this to control the speed of a motor.

555 Police Siren Circuit with Build Instructions

In this tutorial, you’ll learn how to build a 555 police siren circuit using two 555 timer ICs.

The 555 timer is a popular integrated circuit (IC) for hobbyists and can be used for a great variety of projects. For this project, we are going to use it to create sound with a twist!

Instead of a “straight” sound, we are going to make the frequency change automatically so it ends up sounding like a wailing police siren.

How to Make a Dual 5V Power Supply From USB

In this guide, I’ll show you how to build a dual +5V -5V power supply from a standard USB outlet.

The finished dual power supply circuit

Dual power supplies with a negative output taken from the positive output can be a little tricky. It’s not a matter of difficulty, but about the low availability of support for easier ways to do this kind of power supply.

So I’ll show you one of the easiest ways to make a dual power supply (also known as bipolar power supply) using a simple USB connection.

It is fair to mention, that this will be for low-power projects since the IC used for this is not capable of outputting much power.

How To Measure Water Tank Depth Using Ultrasonic Sensor

In this tutorial, you’ll learn how to use an ultrasonic sensor. Specifically, you’ll learn how to use the HC-SR04 module with an Arduino to measure the depth of a water tank.

An ultrasonic sensor is one of those things that some people don’t like getting into just because it sounds complex to use and understand. But the fact is, it’s one of the most accessible and fun accessories for those who like to dabble in microcontrollers.

HC-SR04 Ultrasonic Sensor Front