P25 converting to PT0/1

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Oct 18, 2022
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Hi guys and girls,
a EMS I have been listening to for years on a TRS system has been always transmitting P25 as shown on the screen of my 536. As of 2 days ago many of the EMS talk groups are now transmitting PT0/PT1 as shown again on my screen. This is the first time I have seen PT0/1 with any of my TRS P25 departments.
If the screen shows P25 does this mean P25 phase 1? I know PT0/1 means P25 II with time slots 0 and 1.

Am I right to think that this EMS department is changing over from P25I to P25II?

As you can see on the RR data base it shows P25II. But why now am I seeing PT0/PT1 and before P25.

Any information is appreciated.
 
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garys

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It sure seems so from what you wrote.
 

werinshades

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Hi guys and girls,
a EMS I have been listening to for years on a TRS system has been always transmitting P25 as shown on the screen of my 536. As of 2 days ago many of the EMS talk groups are now transmitting PT0/PT1 as shown again on my screen. This is the first time I have seen PT0/1 with any of my TRS P25 departments.
If the screen shows P25 does this mean P25 phase 1? I know PT0/1 means P25 II with time slots 0 and 1.

Am I right to think that this EMS department is changing over from P25I to P25II?

As you can see on the RR data base it shows P25II. But why now am I seeing PT0/PT1 and before P25.

Any information is appreciated.
You're correct, they switched from Phase 1 to a Phase 2 system. On the 436/536, PT0/PT1 indicates the time slots. It's a little backwards, but PT0 is Slot-1, and PT1 is Slot-2.

To answer the "why" part, is they're increasing capacity on the system, and might have either reprogrammed it recently, or they have new radios that are Phase 2 capable.

If a radio that's only Phase 1 affiliates on the talkgroup, it will revert back to Phase 1 until that radio is no longer affiliating on that talkgroup.
 
Joined
Oct 18, 2022
Messages
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Location
Sydney Australia
Yes thanks guy’s.
what I have noticed today is that other departments that use this TRS system are also changing over to PT0/1 from P25. This TRS system is used for government departments only so I bet in a manner of time all the departments will be using P25II.
 
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I’m right,
what I just found on ã Sydney Australian scanner site.

SUNDAY, FEBRUARY 19, 2023​

PHASE 2 PSN / GRN - UNDERWAY


Hello and Welcome Back... Sad News for owners of Uniden 396T / XT radio scanners as various reports online of Phase 2 GRN currently underway.
The Uniden 396 T /XT are Phase 1 Only
Sadly, If you own a Uniden 396T/XT and the PSN (Ex GRN) suddenly stops working, its possible that your local tower has switched to Phase 2
What is Phase 2?
Phase 2 is UHF 6.25khz 2 Channel send / receive while Phase 1 was 12.5khz single channel..
Cheers
 

n1chu

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Oct 18, 2002
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Farmington, Connecticut
Hi guys and girls,
a EMS I have been listening to for years on a TRS system has been always transmitting P25 as shown on the screen of my 536. As of 2 days ago many of the EMS talk groups are now transmitting PT0/PT1 as shown again on my screen. This is the first time I have seen PT0/1 with any of my TRS P25 departments.
If the screen shows P25 does this mean P25 phase 1? I know PT0/1 means P25 II with time slots 0 and 1.

Am I right to think that this EMS department is changing over from P25I to P25II?

As you can see on the RR data base it shows P25II. But why now am I seeing PT0/PT1 and before P25.

Any information is appreciated.

It’s probably as you surmised, noting that Phase I and Phase II systems can both operate and communicate between the two.
 
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