OP25 TalkGroups, CBP

burkert

Member
Joined
Jun 8, 2025
Messages
10
Reaction score
3
I notice on RRDB that there are many frequencies which are P25, for CBP.

I'd love to add these to my existing OP25/icecast/liquidsoap setup.

That being said, I'm at a loss to locate :

  1. the talk group IDs
  2. The control frequencies.
Can someone point me in the right direction?

Thank you,

Burkert
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
10,265
Reaction score
5,853
Location
Suffolk County NY
Trunked systems use control channels. Those freqs you linked are conventional freqs.
 

burkert

Member
Joined
Jun 8, 2025
Messages
10
Reaction score
3
Thank you, @dave3825

Number 2 in my list was the control frequencies (channels).

Would you happen to know where I can find the Control Channels for these frequencies?

Thank you,

Burkert
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
10,265
Reaction score
5,853
Location
Suffolk County NY
Not sure I follow. There are 2 types of systems. Conventional and Trunked. Only trunked systems use control channels. Conventional use stand alone frequencies.
 

burkert

Member
Joined
Jun 8, 2025
Messages
10
Reaction score
3
Ah, alright. I'm still very new to this.

It was my assumption that as the frequencies are possibly nationwide, that they would likely be trunked. I may be mistaken.

If the frequencies listed are conventional and not trunked, would talk groups exist?

Thank you,

Burkert
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
10,265
Reaction score
5,853
Location
Suffolk County NY
The freqs are nationwide but CBP does not have a nationwide trunked system in place. I believe a default tg of 1 or 4095 may show up.
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
10,265
Reaction score
5,853
Location
Suffolk County NY
I am not positive on the tg. And my op25 skills for conventional are rusty. I would imagine there is a way to enter conventional p25 freqs without programming a tg in. Maybe @boatbod or anyone else with knowledge of P25 conventional programming can answer that.
 
Joined
Oct 22, 2023
Messages
365
Reaction score
227
Location
Dupage Cointy IL
There are no control channels or tg's on the conventional VHF frequencies. just plug the frequency in set it to digital and add the NAC codes. Other than light Ohare traffic the frequencies are pretty dead.
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
10,265
Reaction score
5,853
Location
Suffolk County NY
There are no control channels or tg's on the conventional VHF frequencies.

Every p25 conv freq I monitor has a tg with just about every federal one using a default of 1.

Like I said, not familiar with programming conv p25 in op25 so don't know if you have to enter anything or not.
 

werinshades

Member
Premium Subscriber
Joined
Jan 21, 2002
Messages
6,644
Reaction score
3,179
Location
Chicago , IL
Yeah default 1 TG is set in every Motorola radio using conventional P25 modulation. As far as programming a scanner its not needed.
Yes and no. If you want to program radio ID's and text tag them then yes talkgroup(s) are needed and must be programmed as One Frequency Trunk (OFT in Uniden lingo). If no desire to text tag them, then no as conventional programming will suffice. We have had some discussions across the Uniden threads about changing that so the OFT parameters can be included in digital conventional programming and the OFT programming structure can be eliminated.
 

dave3825

* * * * * * * * * * * *
Premium Subscriber
Joined
Feb 17, 2003
Messages
10,265
Reaction score
5,853
Location
Suffolk County NY
Yeah default 1 TG is set in every Motorola radio using conventional P25 modulation
Have seen 1, ,45, 4095 and 65535 programmed into federal radios. Mostly 1, but not just 1.

As far as regular scanner, yeah, just enter the freq. OP is using OP25, and as previously stated, not sure if one has to enter something or not. I believe if he is using rx.py with out a trunk config he should be good to go.
 

burkert

Member
Joined
Jun 8, 2025
Messages
10
Reaction score
3
Thank you, @ChicagoRadio736 , for noting that the frequencies in question tend to be quiet.

Thank you, @dave3825 , for the suggestion to try rx.py. That would likely be the easiest way to test, as opposed to digging into OP25's configuration files!

I notice from the list of frequencies linked to from the OP that there are also Analog frequencies, listed. As it turns out, I still have in my possession an older (analog) Uniden scanner from the early 1990's. I may dust off that older scanner and try plugging in some of these frequencies.

Thank you, all,

Burkert
 
Top