How can the "Durham Region Works (Alarms)" Data signal be decoded?

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robibaw263

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I see a lot of transmission around ~160 Mhz. Checking their Designation of Emission shows this info:
Their modulation type is `LMR-ANALOG`.

From gqrx I can see they are using NFM.
I have tried a regular NFM demodulation but there is no voice, it's definitely data.
I have also tried piping the audio to multimon-ng and dsd but they didn't help.

Is there a way to decode these on Linux?
 
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ronenp

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How do you check the emission designation ? does your radio decode it or you interprate it yourself from looking at the signal ?
do you hear data ? can you record part of the signal and spectral view of it ? it might help to identify and see what data system it is
 
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robibaw263 said:
I see a lot of transmission around ~160 Mhz. Checking their Designation of Emission shows this info:
Their modulation type is `LMR-ANALOG`.

From gqrx I can see they are using NFM.
I have tried a regular NFM demodulation but there is no voice, it's definitely data.
I have also tried piping the audio to multimon-ng and dsd but they didn't help.

Is there a way to decode these on Linux?
Click to expand...
16 kHz is not NFM, so try FM, then compare the noise to one of the online samples, to ID which digital mode is being used.
 
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robibaw263

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Details of such signal can be seen here:

168.96000 Multiple RM 123.0 PL D Rgn Works Durham Region Works (Alarms) FM Data
Click to expand...

and here:

TAFL Licence Details

Use this online tool to search for frequencies, locations, or licensees. Infomation comes from Industry Canada's database of frequency allocations.
tafl.mckie.ca tafl.mckie.ca

The waterfall looks like this:
https://imgur.com/6XNg2q9

I can't figure out what this signal is? Seems like it includes FFSK.
 
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