SDRTrunk and DMR

[jeepsandradios]

I didn't anything on a quick search so figured I'd ask here with some info.

New system in county nearby that is DMR. Decoding control channel with SDR trunk under details get this -

Activity Summary - Decoder: DMR

Brand:Capacity Max Tier III Trunking
Network:1
Site:6
Network Model: SMALL

Digging further into messages on control channel I see alot of this -

CC:0 SMALL NEIGHBOR NETWORK:1 SITE:3 LCN:1215 CHANID:2431 THIS NETWORK:1 SITE:6
CC:0 SMALL NEIGHBOR NETWORK:1 SITE:1 LCN:680 CHANID:1361 THIS NETWORK:1 SITE:6

I never see LCN for site 6 which is the site that I was monitoring from the site. I know the system has RAS but still would like to get it to decode properly so I can submit is to the database. I am thinking I need to setup something else to get it to trunk. When it changes channels I do get active on a couple of the other channels when looking at them specifically. but it never seems to "trunk" wiuth the settings I have now.

It appears there are 5 frequencies in use and I've had hits on all of them, but only 2 others beside control are active alot when monitoring.

Ideas where to move to ? Ive done a ton with P25 but DMR is pretty new to me.

 

[DSheirer]

You might not see the LCN for the control channel that you're decodign in the control channel messaging. It's kinda redundant information if you're already dialed into the correct frequency. You may be able to calculate the LCN for the frequency that you're decoding if they're using a standard channel raster.

 

[jeepsandradios]

Thanks Denny. I'll keep trying it. I was hoping it would trunk similar top P25. More learning I suppose. Its 5 UHF channels so its not a huge or active system so been a bit hard to figure out.

 

[mtindor]

I didn't anything on a quick search so figured I'd ask here with some info.

New system in county nearby that is DMR. Decoding control channel with SDR trunk under details get this -

Activity Summary - Decoder: DMR

Brand:Capacity Max Tier III Trunking
Network:1
Site:6
Network Model: SMALL

Digging further into messages on control channel I see alot of this -

CC:0 SMALL NEIGHBOR NETWORK:1 SITE:3 LCN:1215 CHANID:2431 THIS NETWORK:1 SITE:6
CC:0 SMALL NEIGHBOR NETWORK:1 SITE:1 LCN:680 CHANID:1361 THIS NETWORK:1 SITE:6

I never see LCN for site 6 which is the site that I was monitoring from the site. I know the system has RAS but still would like to get it to decode properly so I can submit is to the database. I am thinking I need to setup something else to get it to trunk. When it changes channels I do get active on a couple of the other channels when looking at them specifically. but it never seems to "trunk" wiuth the settings I have now.

It appears there are 5 frequencies in use and I've had hits on all of them, but only 2 others beside control are active alot when monitoring.

Ideas where to move to ? Ive done a ton with P25 but DMR is pretty new to me.

On a Motorola CAPMAX Tier III DMR system, typically the control channel is dedicated and typically there are not voice calls on the control channel. And without voice calls, you won't see the application discover the LCN. Your best bet might be to try and copy Sites 1 and 3, which would list the LCN of Site 6 in their neighbor broadcast.

Are you willing to share the frequencies you believe are active on that site, or an idea of your location, or an idea of the system (license) that you believe this system belongs to? That might help others help you.

If you don't want to share in public, maybe a private message (to me)?

 

[mtindor]

@jeepsandradios check your private messages on the forums. I sent you what I suspect the LCNs / LSNs are for each site. Should be right, might be wrong. So I didn't post it here. Give it a try and see how it works out for you.

 

[jeepsandradios]

Wanted to follow up on this. Thanks to Mike for the help. I'm decoding the system now and working to improve some stuff to get some more info for the database.