rtl-sdr for digital and trunkd systems?

W1cjf-1

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Brockton,ma
So i have a rtl-sdr and i am interested in listening to the msp and other towns around me that are on trunk'd systems. Can i use the rtl-sdr to do this or would i need to find a scanner that does it?
 

cg

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You can. You would use TRUNK88 to run the older Motorola system and then DSDPlus to run the digital part.
You will probably learn more about the systems and how they work with the SDR but there is a bunch more to learn about setting it up and running it. TRUNK88 is free and DSDPlus is $25

chris
 

KEWB-N1EXA

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New Bedford,MA
So i have a rtl-sdr and i am interested in listening to the msp and other towns around me that are on trunk'd systems. Can i use the rtl-sdr to do this or would i need to find a scanner that does it?
If you look in the Data base Brockton is in Zone 3 for the State police and they are still Analog Trunk. You can monitor 1 channel at A time on 850 Mhz but to run trunk you would need to monitor both the control channel and the channel with the Analog Voice traffic. That requires you
to run 2 SDR units and the correct software. As for the Police and Fire The Brockton Police are P25 and encrypted on the secure channel but Dispatch is analog an in the open and the fire is open and still Analog. ***Pretty much*** the whole area south of Boston is Analog on the 480 Mhz T Band Still which your SDR would have no issue . For that you can run something free like HDSDR.

Peter N1EXA
 
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garys

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A number of South Shore and other south of Boston police departments are P25 on conventional channels. Off the top of my head Rockland, Whitman, Abington, Holbrook, are all P25 conventional. Plymouth County Sheriff BCI is also digital.

You won't find a lot of digital trunk traffic in this area.

Most of the Brockton PD and FD traffic is analog.

The newest version of DSDPlus can be set up to use one SDR as both control and voice channel. I haven't set mine up that way, but there is plenty of information in the SDR and Digital decoding forum.

If you look in the Data base Brockton is in Zone 3 for the State police and they are still Analog Trunk. You can monitor 1 channel at A time on 850 Mhz but to run trunk you would need to monitor both the control channel and the channel with the Analog Voice traffic. That requires you
to run 2 SDR units and the correct software. As for the Police and Fire The Brockton Police are P25 and encrypted on the secure channel but Dispatch is analog an in the open and the fire is open and still Analog. ***Pretty much*** the whole area south of Boston is Analog on the 480 Mhz T Band Still which your SDR would have no issue . For that you can run something free like HDSDR.

Peter N1EXA
 

silberj

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Vine Grove, KY
You can. You would use TRUNK88 to run the older Motorola system and then DSDPlus to run the digital part.
You will probably learn more about the systems and how they work with the SDR but there is a bunch more to learn about setting it up and running it. TRUNK88 is free and DSDPlus is $25

chris
I would look into SDRTrunk. It's java based (cross platform) Has native P25 decoder (along with others) with installed jmbe library. I've found it decodes much better than DSD+. I am currently running v0.5.0a2 which is doing well.

Also DSD+ is free, their fast lane program costs I believe.


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