Open Source Hardware, Makers and STEM tutorials

Make your own pinhole camera

The pinhole photography has its public, and for that it is necessary a device or a camera with very particular and different characteristics to those of a conventional camera. If you are thinking about creating a home pinhole camera or you are curious to know this kind of devices, we explain you everything in detail in this guide. Both what is a pinhole camera and the procedure to create one by yourself, step by step.

The pinhole camera is the one that does not have optical systems as other cameras, that is to say, it does not have lenses or objectives based on the refraction of the light. Instead of that, they simply have a hole that is in charge of forming the image. That hole is known as pinhole and makes the image look very peculiar by dispensing with that optic.

How to make a Geiger counter

home geiger counter

Three Milles Island, Chernobyl, Fukushima, and even some on national territory such as the Coral-I reactor in Madrid or the Vandellos-I in Catalonia. There are many nuclear accidents that have occurred throughout history, and despite the terrible consequences, it seems that the issue of radiation continues to raise some attraction. But what few people know is that, every day, we are all exposed to natural radiation, both that which comes from outer space and that which comes from the minerals of the earth…

Well, if you want to measure the radiation around you, in this new guide we show you step by step the procedure of how you can build a Geiger counter, that is, a device capable of measuring radioactivity. Basically, it is a device that can measure particles that impact with the sensor, such as ionizing radiation, that’s why it’s called a counter, since it can count the number of impacts and therefore the radiation level of an object or place.

How to make a hammer of Thor or Mjolnir

Homemade Thor's Hammer

For those of you who like superhero comics, or are simply fond of Nordic mythology, in this tutorial we bring you the steps to ‘build your own Thor’s hammer’. Although you may know him from Mjolnir. If you have free time and you want to do DIY, you can create your own hammer with some “magic” features that will bring us the use of free hardware to implement, for example, magnetic attraction.

The truth is that there are several ways to do it, also several materials to work with, and even several diagrams of the circuitry or hardware that we will implement to have different functions for our home hammer. You already know that DIY is free, that you can introduce your own modifications in front of what we show you here, and that the limit is your imagination…

Raspberry Pi launches its own keyboard and mouse; available in Pi stores

Raspberry Pi keyboard and mouse

When I read this news I couldn’t help but remember a comment made by an acquaintance: they have been taking things from the devices until they turn them into mobiles/tablets and now they are adding things to them again to turn them into computers. But thinking about this I am wrong, since the reason for the Raspberry Pi boards is not exactly to make portable devices. In any case, the famous motherboard company has launched two more products: a keyboard and a mouse.

As you can see in the image above, the keyboard design is striking for two reasons: firstly, because it looks very much like a keyboard that Apple would have designed and, secondly, because it includes its own logo in what in other keyboards we would see the Microsoft logo, an image that, as a Linux user, I don’t like to have in my laptop. As we will explain later, both devices are in two colors, but I think the one that looks best if we want to be faithful to Raspberry’s philosophy is the one they have used in their promotional image: red and white.

Coral Dev Board: competition for the Raspberry Pi, but focused on AI

When we talk about computers, everyone thinks of laptops or desktops. We don’t usually consider 10″ mini-laptops or, what we talk about most in HWLibre, boards like the Raspberry Pi or the Arduino. These boards, whose basic package does not include anything else, serve as a brain for almost anything, such as a multimedia center, a speedometer or a spy camera. But what if we need “more brains”? It seems that’s what Google thought of when they launched the Coral Dev Board.

What’s the point of a new plate if this market is dominated by Raspberry Pi and Arduino? More than we could ever think of at first. Today’s boards are intended for use in devices with common tasks. Among these tasks we may have to run an operating system, as long as it is not a very heavy one. Operating systems, which I think is the most complicated thing existing boards can do, can be complex, but they are nothing compared to AI. The Coral Dev Board has been created thinking about the Artificial Intelligence, so that the developers can carry out their projects in this field.

How to create your own guitar amplifier for $5

It seems like only yesterday I started playing the guitar: my mother bought me an acoustic for about 15,000pts (about 90 ? from today) and at that time I didn’t know a single chord. I started to learn classical guitar, but what I liked was bands like Nirvana or MetallicA. It wasn’t until about 4 years later that I had (and still have) my first amp. It was a Fender that was priced out of my month’s salary at the time, about 80,000pts (about $500 now). In those four years I missed having an amplifier to be able to play with “electricity”.

Today there are many more options. In fact, I don’t use my amp anymore. Instead, I connect my instruments to multi-effect pedalboards that go straight to the computer, where I can record and edit whatever I want. But how much are those footswitches worth? There are many prices, but I have two that once cost me between 300 and 500 euros. I explain this because it’s clear that ‘one of the problems of wanting to play with an amplifier is the price of this one or the devices that replace it. In this article we will show you how to create the cheapest mini amp you can imagine.

How to make your own bike speedometer with Arduino

Today, in the 21st century, virtually every vehicle comes with its own speedometer and odometer. This is true for cars, motorcycles, some e-Bikes, etc. In addition, there are also many applications in the different App Stores that will allow us to know how fast we are going and how many kilometers we are doing using the GPS of the mobile device. But what is the problem with these applications? They run on a device that is not always the cheapest. As in almost everything, a solution to the problem could be to ‘create our own speedometer‘.

Everyone knows what an iPhone costs. Personally I have one and for months I was afraid of falling off my bike, more for my phone than for myself. Now I go with a Garmin, but any device of this brand has a price of hundreds of euros, something that many users can not or want to spend. If we know what we are doing, sometimes the best option is for us to assemble our own hardware and in this article we will show you how to ‘build from scratch’ our own odometer.