P25

[Salvatorejrc]

Basic question, but how can I identify phase I vs phase II on the DB?

 

[cmjonesinc]

Some systems are 'phase 2' but not all the talkgroups are. In the database if you see 'D' in the mode column its phase 1. If it's phase 2 you'll see a 'T' for tdma. Most phase 2 systems have a phase 1 control channel and if it has phase 1 talkgroups you can monitor those with a phase 1 scanner. Very very very few systems in the US have a phase 2 control channels which is a different animal. Right now those seem to mostly be some of the newer utility company systems that are rolling out. If you have some specific questions about a system local to you post a link and we can help.

Here's an example

 

[natedawg1604]

Yeah cmjonesinc is correct. There is a huge difference between a system "supporting" phase II, vs. actually using phase II talkgroups. You might have some talkgroups operating in Phase II and others in Phase I. Checking the "T" vs. "D" under the mode column is all you really care about.

 

[Salvatorejrc]

Some systems are 'phase 2' but not all the talkgroups are. In the database if you see 'D' in the mode column its phase 1. If it's phase 2 you'll see a 'T' for tdma. Most phase 2 systems have a phase 1 control channel and if it has phase 1 talkgroups you can monitor those with a phase 1 scanner. Very very very few systems in the US have a phase 2 control channels which is a different animal. Right now those seem to mostly be some of the newer utility company systems that are rolling out. If you have some specific questions about a system local to you post a link and we can help.

Here's an example
View attachment 108753

What about for frequencies that are not apart of a trunked system?

 

[wtp]

stolen from a website
It’s important to realize that Phase 2 is currently only available for trunked P25 operation. For radio to radio and conventional P25 operation, Phase 1 is still used.

so in the RR database under mode you would see P-25 and there is no phase 2 for a non-trunked system (conventional)

 

[Salvatorejrc]

stolen from a website
It’s important to realize that Phase 2 is currently only available for trunked P25 operation. For radio to radio and conventional P25 operation, Phase 1 is still used.

so in the RR database under mode you would see P-25 and there is no phase 2 for a non-trunked system (conventional)

Ah got it. Thanks

 

[wtp]

i think...
it has something to do with the data stream giving the radio the 'timing' for the timeslots.