Øyvind Nydal Dahl

Øyvind Nydal Dahl is an author, maker, and electronics enthusiast from Norway. He holds a master's degree in electronics from the University of Oslo and have been teaching electronics since 2012 through books, workshops, courses and articles. He's the founder of the online electronics academy Ohmify. And he's the author of Electronics For Kids and A Beginner's Guide To Circuits.

Arduino Potentiometer – Circuit and Code Example

This Arduino Potentiometer circuit is a simple example that shows you how analog inputs work, and how you can use the Serial Monitor to learn about what is going on inside the chip.

In this quickstart guide, you’ll learn how to connect a potentiometer to an Arduino board and read out the voltage. This is a great practice circuit when you’re learning Arduino. The code is straightforward and the potentiometer connections are simple.

Parts Needed

Arduino Potentiometer Circuit

To connect a potentiometer to an Arduino, connect the middle pin of the potentiometer to an analog input pin on the Arduino. Then connect the outer pins to 5V and GND.

What is Arduino and How Do I Get Started?

Arduino is a microcontroller board that makes it really easy to program electronics. It’s an easy way to get started with microcontrollers that I highly recommend since it lets you jump right into the code and do stuff from the start.

You can use it both for building simple things like a blinking LED – and advanced stuff like building an internet-connected robot. With Arduino, it’s simple to build really cool electronics projects without learning a bunch of theory. And it’s fun!

It has several inputs and outputs that are controlled by simple commands that you write into a program on your computer.

Arduino UNO board

Open Collector Output – What Is It and How Do I Use It?

An open collector output is not a normal high/low output. Instead, these outputs are connected via a transistor. And the collector of the transistor is available at the pin. For example, if you have a NAND gate with an open-collector output, it will look like this: So when the output from the NAND gate is ‘1’,

Arduino Blink LED – Circuit and Code Example

The Arduino blink LED circuit is a simple circuit that works great for starting to learn Arduino. Both the code and the connections are straightforward so that you can understand it with little to no background.

In this quickstart guide, you’ll learn how to connect an LED to an Arduino board and make it blink.

Parts Needed

Arduino Blink LED Circuit

To connect an LED to an Arduino, you need a resistor in series with the LED. This is to limit how much current the LED pulls out of the Arduino pin. The value isn’t crucial but should be between 220 Ω and 1000 Ω.

How Capacitors Work – A Tutorial For Hobbyists

A capacitor is a basic electronic component that works like a tiny rechargeable battery with very low capacity. Capacitors are used to create oscillators, time delays, add a power boost, and much more.

Like most components, the easiest way to understand how a capacitor works is to see with your own eyes what it does in a circuit.

Electrolytic capacitor

When I started learning electronics as a teenager, this was the first component I learned about. The way my father explained it to me made it easy to understand even though I had no understanding of the basics of electronics.

In this guide, I’ll show you how a capacitor works so that you’ll be able to understand what it does in circuits, and how you can use it in your own projects.

Covered in this guide:

Arduino Laser Module: Connecting KY-008 to Arduino

In this tutorial, you’ll learn how to connect an Arduino laser module to Arduino. I’ve used the KY-008 as an example, but most low-power laser modules will work the same way.

Blinking laser module with Arduino

Table of Contents:

The KY-008 Arduino Laser Module

The KY-008 is a laser transmitter module that creates a dot-shaped laser beam that can be used as a laser pointer or to create mini laser shows. It is compatible with Arduino, Raspberry PI, ESP32, and other popular microcontrollers.

Laser Diode: The Ultimate Beginner’s Guide

A laser diode is a cool component that you can do a lot of fun stuff with, from engraving wood to creating a light show or giving your robot eyes! They range from super cheap (or even free if you can find one in an old CD player!) to more expensive.

Most types are really easy to use too, once you learn the basics. In this article, you’ll learn the basics of laser diodes and how to use them in your own projects. In the end, I’ll show you how to create your own invisible tripwire!

Laser diode illustration

Identify Electronic Components (Quick Reference)

Not sure what type of component you’re looking at? Use this list to identify electronic components and learn what they do. 9V Battery ClipTo connect a 9V battery to your board. BreadboardThe breadboard is a very handy tool for connecting circuits. You can use it to practice, test ideas, or build simple prototypes. Breadboard wiresTo

Phototransistor – A Newbie’s Guide

A phototransistor is an incredibly useful component for detecting light in electronics projects. You’ll often find them in remote-control receivers, pulse oximeters, and line-following robots.

In this guide, you will learn what phototransistors are, how to use one, and with a simple project you can build to create an automatic light on/off switch.

Phototransistor symbol and package

What is an Integrated Circuit (IC)?

An integrated circuit is simply any type of circuit, made to fit onto a small chip. Sometimes referred to as a chip, a microchip, or an IC. It can be a microcontroller, an amplifier, a Bluetooth module, or anything in between.

An integrated circuit made in 2008 by Oyvind Dahl
The integrated circuit I made in 2008

By making a circuit on a small chip, it’s much easier to build advanced projects. Let’s say you want to make a tracking device for your car. You can find a GPS chip for positioning, a GSM chip to send text messages with the position, and a microcontroller chip to control everything. Then create a printed circuit board design to connect them all.

This would be pretty much impossible to do if you were to design everything from scratch with individual components. Integrated circuits make building circuits so much easier!

Back in 2008, I made my own integrated circuit as I was doing my master’s degree at the University of Oslo. So if you want to learn how these tiny and powerful components are actually made, from a practical point of view, (and how you can make one yourself as a hobbyist), read on!

What is a Light-Emitting Diode (LED)?

A Light-Emitting Diode (LED) is a small component that lights up when there is current flowing through it. It’s used in light bulbs, displays, lighting decorations, and much more. In electronics, it’s often used for showing the state (is the gadget turned on?).

You can see the light-emitting diode everywhere! In laptops, on mobile phones, on cameras, on toys, in our car +++.

A green light emitting diode on a breadboard

It’s a type of diode, so it only works when you connect it with its anode towards your battery’s plus terminal.

Chances are you will be working with LEDs a lot when you start learning electronics. They are cheap and simple to use, and it’s a great way to check if your circuit is working properly or not.

What is a Diode? A Guide For Beginners

A diode is a component that lets current flow in one direction and blocks it from flowing in the other direction. It has two pins; anode and cathode.

The diode symbol looks like an arrow pointing toward a line. The line represents the cathode side, and so does the line marking on the diode component itself. In the picture above, the line marking is on the left side, so that’s the cathode side.

Diode symbol and diode markings showing anode and cathode

How To Use A Breadboard – The Beginner’s Guide

A breadboard is a simple and useful tool for connecting a circuit. It’s really useful for beginners as you can easily experiment and test out circuits without soldering. But it’s also useful for more experienced people since you can prototype an idea, or parts of a circuit, quickly.

I often use breadboards in my work.

Want a quick introduction to the breadboard? Check out my short video below (2:30) or continue reading.

Capacitors in Series

Capacitors in series are capacitors that are connected one after the other. The result always becomes a capacitance that is lower than the lowest value. In this guide, you’ll learn why this is the case and how to calculate their combined values. And I’ll also throw in a simple rule of thumb that you can

Capacitors in Parallel

When you connect capacitors in parallel, you connect them alongside each other. And the result becomes a capacitance with a higher value. In this guide, you’ll learn why it works like that, how to calculate the resulting capacitance, and some examples of this in practice. As you’ll soon see, this is actually very simple. How