N3 Software Defined Radio Receiver

I never intended to get into the radio business. However, as with many things in my life, a need to find something just right for my purposes drove me to create something.

I wanted to build tiny satellites to make it simple, reliable and cheap for me and others to carry out experiments in space. So we created ThumbSat.

I wanted some way to grab the data from ThumbSats without relying on large, complex and costly ground stations. So we began ThumbNet, where there are so many stations distributed evenly around the world that they can be small and simple. They can be set up and operated by schoolchildren.

But donating any kind of commercially-available equipment to hundreds of volunteers and schools around the world can rapidly become very expensive. So we designed and built our own radio receivers. The thing is, the only way that we could make those receivers cheap enough was to build lots of them, but we didn’t need all of them. So we decided to sell the surplus, giving a twofold benefit – our radios were cheap, and the sales of surplus could fund the ThumbNet stations. And that’s how I accidentally got into the business of radios.

My globe for recording ThumbNet ground stations – a lot more circles have been added since this photo was taken!

I’m very proud of ThumbNet, because it has inspired the next generation of scientists and engineers around the world, but most importantly because it brings us together. There are no barriers. We do have an online digital map of ThumbNet ground stations, but it feels more right for me to take out my marker pen and proudly inscribe a small circle on an inflatable globe that I keep for this purpose. It connects me to those faraway places. The more places, the better. We have tremendous plans for ThumbNet. Watch this space…

As I said, I didn’t mean to get into the business of developing radios, but my life has provided me with clues that it would happen some day.

For a while, my schoolfriend could pick up radio transmissions through his teeth. Really.

At first I didn’t believe him, but my attitude changed when I followed a book and created my own crystal radio. I was amazed that I could take just 4 simple components and some wire, wind a coil and actually grab the invisible power that was travelling through the air, and turn it into a sound in my ear. Later, radios turned into treasure. At a local radio amateur’s fair, I found a book with cryptic poetic instructions to the location of a gold treasure chest. I found that treasure chest.

During my space career, others have generally taken care of the radio side of things, and it’s only with ThumbSat and ThumbNet that I have been inspired to renew a close, hands-on acquaintance with this fascinating sphere of engineering and science. I’ve been fortunate to be surrounded by a great team who have made all this happen, from the engineering, to the organization, to the general presentation.

N3 Software Defined Radio Receiver internal components

It has been a long journey from that crystal radio set.  Today, we have Software Defined Radio (SDR).  Why software-defined?  Because rather than have a specialised radio that is only useful for a narrow band of frequencies and applications, our radio is very versatile.  It uses the amazing R820T2 and RTL2832U chips to grab all the radio waves over a large frequency range, digitize them and make use of the phenomenal processing power of your computer (the software bit) to allow you to tune in and decode pretty much any radio signal.

Of course, they can be used for listening to radio, but the limit is your imagination – how about space and atmospheric physics? Or working out which exotic country that aircraft above you is heading to? Or ???

And I had to invent a new word for what we’re doing next with these radios.  As with many of my invented words, I’m sure it won’t be long before someone steals it for something else, but here it is anyway – Nongle!  You see, these things are not dongles, they’re Nongles!  We’re splitting the radios back up into separate “building blocks” and adding in some little extras, just because we need them for our own developments. We’ll make the components available to you, and because we buy them in bulk, we’ll pass on the cost savings to you too. This will give you the opportunity you to play, to experiment, to learn, to teach, and we hope – to be inspired.

The spirit of that crystal radio set is in there somewhere.

If you’d like to buy a Nongle and in so doing contribute to our global ThumbNet project to inspire the next generation, that would be great!