Amateur radio enthusiasts in the US will be interested in Faraday, an open-source digital radio that runs on 915 MHz, which amateur radio enthusiasts may know better as the 33 cm band.
You can transmit on 915 MHz without a license (in the US), taking advantage of the Industrial, Scientific, and Medical (ISM) exemption. This means that there’s commodity hardware available for sending and receiving, which is a plus. But you can’t do so with any real power unless you have an amateur radio license. And that’s what makes Faraday interesting — it makes it very easy to transmit and receive digital data, with decent power and range, if you’re licensed. The band is currently under-utilized, so go nuts!
The hardware design and documentation is online, and so is the firmware. The founders of the project would like you to build out a big network of these devices, possibly meshing them together. Our only regret is that the 33 cm band is only really open for use in the US, both with a license and without. Of course, there’s very little the Faraday team can do about that.
We’re no strangers to digital-mode amateur radio around here. But if you’re an amateur who hasn’t played around with digital modes yet, this might be a good way to get your feet wet.