SDR P25 Phase 2 Scanning

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Seanm214

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Hello,
Can someone please help me out by telling me what the best way is to scan P25 phase 2 system on SDR. Specifically trying to monitor the Suffolk county police department trunked system on Long Island NY. I currently have an RTL-SDR dongle. I’m just starting out with SDR and don’t want to break the bank by purchasing a phase 2 digital trunking scanner. What software and programs are needed to monitor phase 2 P25 and is an RTL-SDR dongle going to work for this?
Thanks,
Sean
 

GTR8000

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Note that the bulk of the Suffolk County PD activity still takes place on the SmartZone system, not the P25 system. Also, so far all of the talkgroup activity on the P25 system is FDMA (Phase I), not TDMA (Phase II). The system is capable of Phase II, but that hasn't yet been observed.

In any event, DSDPlus Fast Lane is your best bet. $10 donation and it runs on Windows.
 

air-scan

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Hello,
Can someone please help me out by telling me what the best way is to scan P25 phase 2 system on SDR. Specifically trying to monitor the Suffolk county police department trunked system on Long Island NY. I currently have an RTL-SDR dongle. I’m just starting out with SDR and don’t want to break the bank by purchasing a phase 2 digital trunking scanner. What software and programs are needed to monitor phase 2 P25 and is an RTL-SDR dongle going to work for this?
Thanks,
Sean

You need another dongle. Run 2 dongles. That system is pushing the very edges of 1 dongles 2.40 msps limit. Trust me I had tried the 1 dongle method on the local P25 PII system and all i get was bad audio. Use SDRTrunk and build the required JMBE Library to be able to hear PII TDMA audio. https://github.com/DSheirer/sdrtrunk

Trust me SDRTrunk sounds better than DSPlus FL


SDRTrunk is totally free

If you want you can pay $10 for DSD+ FL it does other modes like DMR, D-STAR, Provoice and NXDN where SDRTrunk does not.

As for APCO P25 PII TDMA I recommend SDRTrunk.
 
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GTR8000

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You need another dongle. Run 2 dongles. That system is pushing the very edges of 1 dongles 2.40 msps limit. Trust me I had tried the 1 dongle method on the local P25 PII system and all i get was bad audio. Use SDRTrunk and build the required JMBE Library to be able to hear PII TDMA audio.
Two dongles are not necessary with DSDPlus Fast Lane single-dongle mode. It works perfectly fine, and is much easier to get up and running than SDRTrunk. Also, he doesn't yet need Phase II capability as I noted above.
 

air-scan

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Two dongles are not necessary with DSDPlus Fast Lane single-dongle mode. It works perfectly fine, and is much easier to get up and running than SDRTrunk. Also, he doesn't yet need Phase II capability as I noted above.
That link says specifically APCO P25 Phase II

System Name:Suffolk County (Project 25)
Location:Suffolk County, NY
County:Suffolk
System Type:Project 25 Phase II
System Voice:APCO-25 Common Air Interface Exclusive
 

simmsrep

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Since Suffolk County is still using the SmartZone system he's going to need Unitrunker for that. Neither DSDPlus or SDRTrunk will decode that. But for the P25 SDRTrunk needs 2 dongles but other than that no more cost. DSDPlus needs only 1 but will need fastlane which starts at $10 but you get a lot more than P25 with DSDPlus. Well worth the investment. SDRTrunk is still being actively developed (DSDPlus also) and I agree with @air-scan it has the best phase 2 decoding and sound quality. None of the talkgroups shown are using phase 2 though.
 

GTR8000

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That link says specifically APCO P25 Phase II

System Name:Suffolk County (Project 25)
Location:Suffolk County, NY
County:Suffolk
System Type:Project 25 Phase II
System Voice:APCO-25 Common Air Interface Exclusive
The system is Phase II capable, however all of the talkgroups so far are operating in FDMA mode. Just because a system is listed as Phase II does not mean it is exclusively TDMA, you must look at the individual talkgroups to determine what mode they're operating in. Go back and read my first post, I explained it clearly.
 

air-scan

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The system is Phase II capable, however all of the talkgroups so far are operating in FDMA mode. Just because a system is listed as Phase II does not mean it is exclusively TDMA, you must look at the individual talkgroups to determine what mode they're operating in. Go back and read my first post, I explained it clearly.
I stand corrected. I forgot about the "T" for TDMA and"D" for FDMA in the tone column in the database.
 

boatbod

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Another option is OP25, if you are Linux-savy (or willing to become so). Runs great on a Raspberry Pi.
Yup. Single dongle for op25 P25 trunking, two dongles if you want to try your luck with Smartzone tracking. The latter has not been formally announced as it's still in development, but it has been found to work reasonably well for both analog and digital on the 3 test sites that it is currently deployed.
 

Seanm214

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Note that the bulk of the Suffolk County PD activity still takes place on the SmartZone system, not the P25 system. Also, so far all of the talkgroup activity on the P25 system is FDMA (Phase I), not TDMA (Phase II). The system is capable of Phase II, but that hasn't yet been observed.

In any event, DSDPlus Fast Lane is your best bet. $10 donation and it runs on Windows.
Thank you. I didn’t realize that.
 

Seanm214

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Note that the bulk of the Suffolk County PD activity still takes place on the SmartZone system, not the P25 system. Also, so far all of the talkgroup activity on the P25 system is FDMA (Phase I), not TDMA (Phase II). The system is capable of Phase II, but that hasn't yet been observed.

In any event, DSDPlus Fast Lane is your best bet. $10 donation and it runs on Windows.
I am probably better off buying a phase 1 scanner then because they are a lot cheaper.
 

Seanm214

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Since Suffolk County is still using the SmartZone system he's going to need Unitrunker for that. Neither DSDPlus or SDRTrunk will decode that. But for the P25 SDRTrunk needs 2 dongles but other than that no more cost. DSDPlus needs only 1 but will need fastlane which starts at $10 but you get a lot more than P25 with DSDPlus. Well worth the investment. SDRTrunk is still being actively developed (DSDPlus also) and I agree with @air-scan it has the best phase 2 decoding and sound quality. None of the talkgroups shown are using phase 2 though.
Thank you for replying. Do you think that I’m just better off buying a phase 1 scanner since they are cheaper and will be compatible with Suffolk county system?
 

simmsrep

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Thank you for replying. Do you think that I’m just better off buying a phase 1 scanner since they are cheaper and will be compatible with Suffolk county system?
The P25 system is being setup for phase 2. If you get a phase 1 scanner it's only going to last until they get their phase 2 system in operation. Maybe you could ask in the New York forum and somebody will have some input on how long this will be. If you are going to buy a scanner I would recommend a phase 2 capable scanner.
 

Seanm214

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The P25 system is being setup for phase 2. If you get a phase 1 scanner it's only going to last until they get their phase 2 system in operation. Maybe you could ask in the New York forum and somebody will have some input on how long this will be. If you are going to buy a scanner I would recommend a phase 2 capable scanner.
Thank you for your input
 

hiegtx

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Thank you for your input
Besides the fact that your target county, eventually, will change to Phase II, if you plan to take your scanner with you when you travel, you are almost guaranteed to run into a full Phase II system if your trip takes you to, or through, one of the larger metro areas.
 

boatbod

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I wouldn't waste money on a ph1-only scanner - it will seriously dissappoint you esspecially if you have any simulcast in your area.
 
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