How to Build an Arduino Theremin

In this short tutorial, you will learn how to build an Arduino Theremin. You only need three components plus the Arduino, wires, and breadboard.

Use the breadboard diagram or the video below to see how to connect everything.

Simple VU-Meter Circuit

I put together this Voltage Unit (VU) meter using LEDs on a breadboard the other day. It only has 4 LEDs, but can easily be expanded to more:

It’s basically a simple display for showing a value. It’s originally for showing signal level in audio circuits, but there’s no reason you can’t use it to show temperature, rain intensity, light level, or whatever other value you are measuring.

Build Instructions: The Blinking Light Circuit

Do you want to build a circuit that blinks a light? This inverter-based circuit is simple, and it’s small enough to fit on a breadboard.

The circuit uses standard basic electronic components and you can build it even if you have never built anything before. Check out the full build instructions in the video below:

Scroll down to find the complete circuit diagram, component list, and step-by-step instructions (in text-form) on how to build this circuit.

Build an Atari Punk Console this evening

Do you want a fun and easy-to-build circuit? Here’s the simple, but fun Atari Punk Console – with schematics and parts list. It’s a quick build, so you can easily build it during an evening.

It takes its name from the old Atari computers of the 80s because it makes similar sounds.

And after my (not-so-intense) research (I basically just read about it on Wikipedia), I’ve come to learn that the circuit was first published in a Radioshack magazine in 1980.

Here’s a short clip of me playing with the circuit I built:

The circuit that makes sound

“The music that we are hearing is actually 8 seconds old”

That was my friend’s claim.

My friends and I were about 13 years old, and we heard loud music coming from a big event about 3 kilometers away.

“The speed of sound is 340 meters per second, and the event is 3 kilometers away. So that means what we are hearing now is actually what they played 8 seconds ago at the stadium” our friend told us.

I found it hard to accept because I didn’t know too much about sound and how it worked.

But our friend was really good at memorizing facts.

And he was right.

Blinking Christmas Lights


Christmas is coming up, so why not set aside an hour or two to build this blinking Christmas lights circuit?

This circuit is easy to build and it’s something you can put to use right away. I built this and hung it in the window, something my girlfriend loved!

The blinking part of the circuit is made up of only 4 components. Then you’ll add as many lights as you want.

Build The Knight Rider Light Bar Circuit With LEDs

The knight rider light bar circuit creates a running light similar to the light bar on the car from the 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 I was a part of. Unfortunately, I broke it the first day because I increased the voltage too much, but that’s another story.

You can build this circuit if you’re a total beginner, but of course, it’s a bit easier if you have already built a few circuits before.

Installing Whatsapp on Intel Galileo

Whatsapp on an Intel GalileoIn this tutorial I will show you how to install Whatsapp on your Intel Galileo. I’ll also show you how to read sensor data easily from your mobile phone through Whatsapp.

You can easily extend this into whatever you want, so that you can control your DIY electronics with your smart phone.

I used a Grove Soil sensor together with an Intel Galileo for this project. But you can use whatever sensor you want, as long as it connects to the ADC of your Intel Galileo.

DIY Weather Station with Intel Galileo

dht11-sensorYour own DIY weather station is very useful if you for example want to optimize the growing process of your plants.

It gives you the possibility of getting real-time data or statistics about things the soil moistness, or the temperature around your plants.

In this tutorial, I will show you how to build your own DIY weather station using the Intel Galileo and a few sensors.

Intel Galileo Board for Measuring Rain and Moist

intel galileo boardIn this Intel Galileo board sensors tutorial you’ll learn how to use analog sensors. I’ll show you how to use a simple rain sensor and a soil moisture sensor.

This project could be used on a farm: To make better decision about when to water the crops, it’s very helpful to have information about how much it has rained, and the moisture level in the soil.

Even though I used an Intel Galileo here, you could just as well use the same code and connections with an Arduino.

The components I used:

How To Boot Intel Galileo From an SD-card

SD card on an Intel GalileoTo get access to more interesting functionality, you need to boot Intel Galileo from an SD-card.

The on-board Linux version running on the Galileo is very limited. So to get access to things like WiFi communication (through Mini-PCIe), you need to install a proper Linux version on an SD-card.

This will also give you access to lots of other libraries, so that you can create programs for example in Python or Node.js.

Another advantage is that if you boot from an SD-card, the sketch you upload to the board does not get erased when you power off the board (as it does if you are using the on-board Linux).

I wanted to try this, because I wanted to build a more advanced weather station than my simple weather station. When booting from an SD-card, I can easily create a web server that runs in the background. Then give easy access to sensor values from an external computer.

This Mono Amplifier Circuit is Super Easy To Build

PCB Layout of the mono amplifier circuitThis is the easiest mono amplifier circuit to build, as far as I know.

I love it because it is powerful enough to play pretty loud. And it doesn’t need a pre-amp, heat-sink or any weird transistors.

All it requires, is a few standard capacitors, a couple of resistors and a potentiometer.

It will give you 4.7 Watts of power. This should be enough to play music in the park with some friends and a couple of brewskies.

I’ve added the schematics, PCB design and Gerber files a little further down the page.

Ho, ho ho! 5 Christmas Circuit Ideas

Every Christmas I turn into a child again.

I have a hard time falling asleep. I wake up early in the morning to watch cartoons. And I am probably even more curious about the gifts under the tree than my two-year-old nephew.

I often get emails asking for project ideas.

So I thought I’d share a few Christmas circuit ideas today.

Christmas tree