How to find P25 Control Channel for Springfield, MA

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drsprite

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Hi there, I'm looking for the P25 control channel for Springfield, MA. I don't see it listed in the database, only that they've switched to P25. The 460.1000 freq listed doesn't seem to be valid for control as best I can tell.

Is there a way to find that in SDR Sharp?

I'm using 2 RTL SDR USB sticks, and am following this tutorial on how to have 1 USB as control and 1 USB as voice. So far nothing is working - and I think it's because I can't find the control channel.

Tutorial: P25 Trunked Tracking and Decoding with Unitrunker and DSDPlus | Jeffrey Kopcak, MBA | Page 5

Radio Reference Database: https://www.radioreference.com/apps/db/?ctid=1219
(Springfield listed as P25, but not listed in the "All Trunked Radio Systems in Hampden County" section)

Any help is appreciated.
 

drsprite

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Update: I've been able to manually decode some voice on 460.1309 and 460.5804 (my ppm corrections may be slightly off here), so I'm going to assume the control channel is around this range somewhere?

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RDGDigital

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Mar 27, 2012
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P25 is a standard for digital communications and is not limited to just trunk systems. It can also be used on conventional frequencies. I'm not familiar with MA but I believe what the database is saying is that those frequencies (the ones marked as P25) are using digital communication on these frequencies and not that they are part of a trunk system.

And, I'm not an expert (in fact I'm not even a novice) so you may want to wait for others to chime in on this subject.
 

bailly2

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they switched from analog to digital, didn't move to a trunked system. just these 3 frequencies 460.1, 460.45, 460.5
 

drsprite

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Jun 7, 2011
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Okay, interesting. Maybe it's my ppm correction offset that's wrong. I'm getting good voice on 460.130, where that voice should be on 460.100.

This is what made me think it was trunked.
 

ecps92

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Taxachusetts
Springfield is P25, but Conventional not Trunk.

The Trunk out your way is the Commonwealths

Hi there, I'm looking for the P25 control channel for Springfield, MA. I don't see it listed in the database, only that they've switched to P25. The 460.1000 freq listed doesn't seem to be valid for control as best I can tell.

Is there a way to find that in SDR Sharp?

I'm using 2 RTL SDR USB sticks, and am following this tutorial on how to have 1 USB as control and 1 USB as voice. So far nothing is working - and I think it's because I can't find the control channel.

Tutorial: P25 Trunked Tracking and Decoding with Unitrunker and DSDPlus | Jeffrey Kopcak, MBA | Page 5

Radio Reference Database: https://www.radioreference.com/apps/db/?ctid=1219
(Springfield listed as P25, but not listed in the "All Trunked Radio Systems in Hampden County" section)

Any help is appreciated.
 

drsprite

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Jun 7, 2011
Messages
39
Great, thanks! Still working on fine tuning this SDR, but making progress. Sometimes the decoded packets aren't quite as clear as I'd hope they'd be
 
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