Voice on P25 Phase 2 TDMA System

[Coolant113]

I am looking to set up a system that decodes, logs, and records the voice on a P25 Phase 2 TDMA system. The last time I looked into doing so about a year ago, I found out that Unitrunker 2.X does not support TDMA systems. I am looking for some direction on as to what software components I will need in order to get this up and running. Note I am using a Windows machine. Any direction would be appreciated.

 

[GTR8000]

SDRTrunk will decode and record the voice. Combined with Trunking Recorder you have an easy way to listen to the audio. For activity logging alone, Unitrunker 2.1 is unrivaled. You're probably going to want to dedicate one dongle to Unitrunker to sit on the control channel logging activity if it's that important to you, the other dongle(s) for SDRTrunk (depending on how much bandwidth needs to be captured for the site you're interested in). You can also pair up SDRTrunk with an SDRPlay RSP1A or RSP1B to capture up to 8.5 MHz of bandwidth. Airspy R2 or Airspy Mini are also options, however I would recommend the SDRPlay over either Airspy model as it a) captures more bandwidth than the Airspy Mini and b) captures the same bandwidth as the Airspy R2 but costs less.

Oh and just to be clear, Unitrunker can decode P25 FDMA control channels, which is what 99% of P25 Phase II systems use, so it can log the activity for TDMA talkgroups, it just can't decode the TDMA audio.

 

[Coolant113]

SDRTrunk will decode and record the voice. Combined with Trunking Recorder you have an easy way to listen to the audio. For activity logging alone, Unitrunker 2.1 is unrivaled. You're probably going to want to dedicate one dongle to Unitrunker to sit on the control channel logging activity if it's that important to you, the other dongle(s) for SDRTrunk (depending on how much bandwidth needs to be captured for the site you're interested in). You can also pair up SDRTrunk with an SDRPlay RSP1A or RSP1B to capture up to 8.5 MHz of bandwidth. Airspy R2 or Airspy Mini are also options, however I would recommend the SDRPlay over either Airspy model as it a) captures more bandwidth than the Airspy Mini and b) captures the same bandwidth as the Airspy R2 but costs less.

Oh and just to be clear, Unitrunker can decode P25 FDMA control channels, which is what 99% of P25 Phase II systems use, so it can log the activity for TDMA talkgroups, it just can't decode the TDMA audio.

Thanks for the information. I will attempt to do this setup. What is the difference between the SDRPlay RSP1A and RSP1B? To clarify I am using the Airspy R2.

 

[Whiskey3JMC]

What is the difference between the SDRPlay RSP1A and RSP1B? To clarify I am using the Airspy R2.

Click the details and read for yourself. One major difference is the 1B's steel case

Products - SDRplay

Our Products

www.sdrplay.com

 

[GTR8000]

Thanks for the information. I will attempt to do this setup. What is the difference between the SDRPlay RSP1A and RSP1B? To clarify I am using the Airspy R2.

If you already have an Airspy R2, you'd want to use that with SDRTrunk to do the voice decoding. Pick up a cheap RTL dongle for Unitrunker to do your activity logging.

 

[enosjones]

Unitrunker will only decode Phase 1, not phase 2, dsdplus will decode either one

 

[GTR8000]

Unitrunker will only decode Phase 1, not phase 2, dsdplus will decode either one

We've already established what Unitrunker is capable of, and DSD+ is inferior as compared with SDRTrunk, especially if the OP wants to record all voice activity simultaneously.

 

[AngWay]

SDRTrunk will decode and record the voice. Combined with Trunking Recorder you have an easy way to listen to the audio. For activity logging alone, Unitrunker 2.1 is unrivaled. You're probably going to want to dedicate one dongle to Unitrunker to sit on the control channel logging activity if it's that important to you, the other dongle(s) for SDRTrunk (depending on how much bandwidth needs to be captured for the site you're interested in). You can also pair up SDRTrunk with an SDRPlay RSP1A or RSP1B to capture up to 8.5 MHz of bandwidth. Airspy R2 or Airspy Mini are also options, however I would recommend the SDRPlay over either Airspy model as it a) captures more bandwidth than the Airspy Mini and b) captures the same bandwidth as the Airspy R2 but costs less.

Oh and just to be clear, Unitrunker can decode P25 FDMA control channels, which is what 99% of P25 Phase II systems use, so it can log the activity for TDMA talkgroups, it just can't decode the TDMA audio.

when using sdrtrunk to decode TDMA and phase 2 i notice it's not showing a yellow control channel that it's locked onto it's just showing two IDLE and when traffic starts one turns blue to CALL. is that how it's suppose to do?