136-174 / 400-470 / 700-800 MHz
P25 phase 1
The talkgroup, the radio id and the key a call is under, off the C4FM frames North American public safety runs on.
P25 phase 1 frames carry the talkgroup and the source radio id in clear whether or not the voice payload is encrypted, which means the pattern of who talks to whom is readable on a system you cannot listen to.
Where a call is encrypted, the algorithm id and key id are read and the call is listed in the keys view rather than silently dropped. An unencrypted system shows the same rows with the audio attached.
What comes out
- Talkgroup and source radio id
- NAC, the network access code identifying the system
- Algorithm id and key id on an encrypted call
- Call length and the channel it ran on
No speech yet: the frames are read for who and what, not for audio.
$ waveshark --tune 453.5 --callsRead next
Something did not decode?
Record the burst with --record and open an issue with the capture. A capture that decodes becomes a test fixture.
Open an issue