Listening to D-STAR Digital Voice with DSD 1.7
D-STAR or (Digital Smart Technologies for Amateur Radio) is a Frequency Division Multiple Access (FDMA) Gaussian Minimum Shift Keying (GMSK) digital voice and data protocol used in amateur radio.
Up until recently it was possible to decode D-STAR headers using either DSD 1.6 or dstar.exe and an RTL-SDR, but it was not possible to decode voice. Now amateur radio hobbyist PU2VLW has brought to our attention that the latest DSD development version 1.7 is capable of decoding D-STAR audio (his post is in Portuguese so we suggest using Google translate). He shows a video of some example D-STAR decoding which we show at the end of this post.
DSD 1.7 can currently be downloaded as source from it’s GitHub respository. Instructions for installing DSD 1.7 on Linux can be found on the post by PU2VLW and the GitHub readme. PU2VLW built DSD 1.7 in Ubuntu 10.04, noting that newer versions of Ubuntu have removed OSS (Open Sound System) support which DSD requires. He then runs SDR# on a Windows PC, tuned to a D-STAR signal, and uses an audio out cable to connect the Windows PC’s audio out to the Ubuntu PC running DSD 1.7.
Update: See this post for installing DSD 1.7 on Windows.
EDIT: There is now a version of DSD+ that can decode D-STAR. https://www.rtl-sdr.com/dsd-version-1-5-released/
Have tried months to get this to work. Several machines, downloads, dongles, just cant get dsd to run. I get lost on discussions of CGYWIN and compiling and DSD+ versus DSD 1.7 …I have SDR# runnign OK, I have VB audio running ok, But cant seem to get the right software on the DSD 1.7, just terrible out on the web, too many bad virus’ed up download sites. To bad not just an easy to install package ?? ideas? Thnks JH
You can often use the “Mono Mix” (or “Stereo Mix”) input device on a Windows machine, and not need VAC or other virtual cable drivers. It works well like that with SDR# and dlFldigi for HAB tracking, both running on the same Win7(32) machine.
It is possible to compile the DSD 1.7 sources for Windows using Cygwin. So it should be possible to decode D-Star voice, using only one Windows machine, using SDR#, VAC and DSD 1.7 compiled for Windows.
Unfortunately, I am not so familiar with the whole cmake and gcc stuff, so my attempt to do this failed. It would be highly appreciated, if someone could build DSD 1.7 for Windows, using the GitHub code and Cggwin and then share the DSD 1.7 .exe with the community.