SDR, DSD P25, Linux vs Windows
I run Linux Mint mostly and gave up on piping GQRX to DSD for P25. GQRX is great for analog but I also jumbled a Linux OS trying to make it all work. I tried the complex setup for SDR Trunk in Linux and after a few hours, (failed scripts, build fails,etc) I was sure it wouldn't work at all, but it did sort of work. I could use it like Unitrunker (under Windows now) to see the calls, but it would not stay on the control channel for very long, it would change the control channel frequency at random times by itself, no matter how many times I corrected it, a second later, it changed the numbers I entered by itself and lost my control channel. I gave up on the audio decoding. I also wasn't keen on how it displayed the talk groups info, it shows a bit more of the P25 technical handshake logs info and Motorola (system WAN calls), but Unitrunker on Windows is the King. I am using the RTL2832 SDR/SMART dongles with Win 7 there. But only to "see" the system data coming in.
As for using Unitrunker and DSD Plus in Windows 7, for P25 (Phase 1) decoding, I spent days fiddling with it and would only get open squelch and no calls. After muting the control channel and adusting squelch for the voice channels (biggie) all I still got was piss poor robotic audio (with echo). I had installed the VB Virtual Audio cable driver too and it was playing nicely with Windows, and two of the RTL2832 dongles, but I had to open all of the windows mixer audio levels and play roulette with the all of the sliders. One stereo mix level cannot be above 1% or you just get squelch noise. But I was getting calls. The end result was still just sporadic P25 decode with crappy robotic illegible audio with a good antenna feed running into each dongle. It was allegedly working as it should, decoding calls and I had perfect waves on the scopes for both control channels and voice channels when they appeared and I could see the DSD decode stream working fine. I was also getting encrypted channels (muted of course) that I didn't want to hear and all the Pace Transit Buss talk groups that I could honestly live without and the rest of the assorted talk groups medley that I don't want to hear either. Cute. But this Does NOT make it a real scanner! More like an experiment. Useable? For Monitoring P25? No Way. YMMV. I think of it as just a time sink for now. I have used Kali Linux (Debian) to crack some WiFi APs, but not as a daily distro. But since it runs on Debian, I don't see why it wouldn't work the same as a plain Debian distro, that's what it is.