Hey there everyone. I was wondering if it would be possible to truly track a OP25 Simulcast system using multi_rx.py. Like just have one SDR Stay on the control frequency and have the other Tune around. Let me know if this is possible or if Im just crazy. Right now I have it set up but its just constantly getting either different talkgroups that are connected and giving me an echo, or its two simultaneous talk groups and its impossible to hear.Thanks!
Yes it's possible but not necessarily required.
With P25 there is signaling on both the control channel and voice channels so the application will always have a complete picture of what calls are in progress regardless of whether it is monitoring the CC or actively decoding audio. OP25 has a tgid priority feature which will allow you to define whether calls for one or more tgids should preempt other calls that are already in progress. By default, all tgids are prio 3 so no preemption takes place.
The purpose for being able to define multiple 'channels' with multi_rx.py is to enable separate whitelist groups of tgids to be handled by separate streams. i.e. Sending multiple feeds to broadcastify. You can also define shared or multiple SDR devices and track multiple P25 systems simultaneously.
I suspect the reason that you are hearing echo is because both your channels are running wide open with no whitelists and therefore receiving the same tgids at more or less the same time. Add whitelists/blacklists and you should b good to go.
