There’s not much need for recording today on Amateur Radio DMR as it’s already being done for many talkgroups on the Brandmeister network. You can simply visit https://hose.brandmeister.network/3127/ and listen to an archive of all traffic from the Minnesota Statewide talkgroup. Click archive from the banner or menu above the main area of the page. No need for anything but an Internet connection, web browser and speakers. If however you are interested in recording something else or if access to these recordings is threatened, here’s an option for you.
DSDPlus software provides the ability to decode many digital formats. From APCO-25, D-Star, EDACS, NXDN, C4FM, QPSK, OpenSky, GFSK, Phase2, NEXEDGE, IDAS, honestly I had no idea we had all these protocols out there. Cool thing is this one software package does all that and of course DMR radio. You can find DSDPlus which is Windows only but known to work under emulators like WINE, or instead run the opensource version which runs on almost anything named just simply DSD software. DSD stands for Digital Speech Decoder. To make this work, you need to capture a baseband audio feed from a tuner. You could do this with a scanner that supports discriminator audio or even simpler, check out the SDR or software defined radio options. For as little as 8 bucks, you can add an SDR radio dongle known as an RTL-SDR directly to a USB port on your computer.
Stay tuned here as I’d like to teach a class on using the RTL-SDR radio devices.
Rather than duplicate the excellent work of others, here’s a nice article that explains the process of connecting this all together. http://www.rtl-sdr.com/rtl-sdr-radio-scanner-tutorial-decoding-digital-voice-p25-with-dsd/