OP25 feature update

[boatbod]

To run multi_rx.py you absolutely need to have a proper cfg.json file. The smartnet_example.json file is included as a starting point and should be used as a template for your own custom config. There are also some Readme files located in the same directory which you may find useful.

You will also need 2 RTL devices because op25 has to monitor the control channel all the time, unlike p25 system where signaling on the voice channel can be used instead.

Is the system you want to monitor 800Mhz rebanded? If so you won't have much work to do beyond setting the control channel frequencies. If it's vhf/uhf you'll also need to define the bandplan using base/offset info from RRDB.

PM me if you get stuck.

 

[W4KRR]

boatbod,
I got it working. I had to tinker with some settings in the .json file.

I noticed a couple of things: The active talkgroup doesn't appear on the bottom of the screen like it does while monitoring P25 systems. Plus, I tried to make a file to show talkgroup aliases, but I can't get it to work. What is the format of that file? Also, talkgroup hold doesn't appear to work.

 

[boatbod]

boatbod,
I got it working. I had to tinker with some settings in the .json file.

I noticed a couple of things: The active talkgroup doesn't appear on the bottom of the screen like it does while monitoring P25 systems. Plus, I tried to make a file to show talkgroup aliases, but I can't get it to work. What is the format of that file? Also, talkgroup hold doesn't appear to work.

The trunk-tags file is the same format tag separated value (.tsv) as it is for the old rx.py. It's 3 column [tgid]<tab>[description]<tab>[priority] with the 3rd column being optional and defaulted to '3' if not specified.

Under multi-rx the terminal behaves a little differently than regular rx.py. Use the left/right arrow keys to cycle between the control channel and the voice channel(s). The control channel will always stay fixed in a smartzone system, whereas the voice channel(s) will hop about following the voice traffic. On the second from bottom line you'll see [0], [1], [...] where the numeric corresponds to the sequential id number assigned to each of the 'channels' defined in the cfg.json file. This same number is used in the stderr.2 log so you can correlate log activity with specific channels if you have more than one defined.

As an aside, if you use multi_rx for P25 and have more than one voice channel defined for a common P25 system, one of the inactive channels (if available) will be auto-assigned to watch the control channel until it is needed for voice decoding.

 

[W4KRR]

I got it working on the Smartnet system, including displaying the currently active talkgroup and alias at the bottom of the display. The only issue now is that the the active talkgroup display and audio disappears every couple of seconds. Almost like a scanner's audio being interrupted by the priority being turned on. I'm thinking there may be an adjustment in the .json file I can try.

I don't think it's signal strength; I'm only a couple of miles from the tower.

 

[boatbod]

I got it working on the Smartnet system, including displaying the currently active talkgroup and alias at the bottom of the display. The only issue now is that the the active talkgroup display and audio disappears every couple of seconds. Almost like a scanner's audio being interrupted by the priority being turned on. I'm thinking there may be an adjustment in the .json file I can try.

I don't think it's signal strength; I'm only a couple of miles from the tower.

You could turn the logging up to "-v 10" and then it'll be possible to see whether the call is being expired (timeout), released, or something else entirely. Be warned that -v 10 generates large log files, but you only need to run it for long enough to capture the scenario.