Phase 2 Question

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milcom_chaser

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So if I park the WS-1080 on the voice channel of a P-25 phase II system. Why won't the radio decode the voice channel? What is it about Phase II decoding that works as a programmed system (control and voice channels) vs
listening to just the voice channel?

Is the data containing the voice passed to the control channel, and the radio decodes it from there?
 

DonS

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To decode Phase II TDMA voice, the WS1080 requires slot number, NAC, WACN ID, and System ID. It gets those from the control channel.
 

whsbuss

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Bingo! There is your problem. Uniden and Whistler scanners are useless in many locations for a simulcast system. Much has been written here on that subject. Start searching ;)
Will we ever get a scanner that handles simulcast?
 

milcom_chaser

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Bingo! There is your problem. Uniden and Whistler scanners are useless in many locations for a simulcast system. Much has been written here on that subject. Start searching ;)
I've not had that experience on such a pandemic level. However, in regards to the thread, seems DonS had a
helpful answer:

"To decode Phase II TDMA voice, the WS1080 requires slot number, NAC, WACN ID, and System ID. It gets those from the control channel."

Meanwhile, thanks for chiming in.
 

troymail

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I don't think the original question has anything to do with simulcast issues....

For a P25 Phase 1 (or legacy Motorola system) trunk voice frequency, the frequency is being used entirely for the signal and the radio can process it just fine.

P25 Phase 2 results in the frequency being "split" into time slices that requires the control channel to determine what slice/slot is being used for what at any given time.

There's no such thing (to my knowledge) as "conventional" P25 Phase 2 so (again, to my knowledge) no scanner (or commercial radio?) decodes a P25 Phase 2 signal in conventional mode.
 
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