Hm, I missed the fact that UniTrunker is required for frequency hopping, there is OpenTrunker, but it doen't seem very active. However, there have been reports [1] of UniTrunker running with wine.

Apart from that, you should be able to follow the directions in the OP. You can use SDR# or more straight-forward, rtl_fm, (forget about the later, it doesn't allow to switch frequencies without restarting, but this should be possible with rtl_tcp) now with PulseAudio it should be possible to redirect the audio from those applications to dsd, but that seems to expect something like /dev/audio - I don't know how to provide that with PA.

[1] http://forums.radioreference.com/trunking-control-channel-de...

Ok, turns out there really is some additional research/instructions required to get this running on Linux…