MotoTRBO Connect Plus Monitorring

[thrivestorm]

Several local departments are switching over to a new UHF MotoTRBO Connect Plus regional system owned by a private company. Is there any legal way to monitor this system? Thanks.

 

[tvsjr]

DSD+ will work, assuming they aren't encrypted.

 

[thrivestorm]

It's not encrypted and I do have DSD+, but how do I follow the trunking nature of Connect Plus? I know Unitrunker will identify it but can not follow the voice due to TDMA, correct?

 

[Bill_G]

Video instructions goodness

 

[thrivestorm]

Thanks for the video. It is a great resource. How can I use this to follow a Connect Plus trunked system with only decoding one talkgroup?

 

[Forts]

Your best bet would be with a DMR radio. It'll be very difficult to do with DSD and a scanner (not impossible, just difficult).

 

[thrivestorm]

I have a DMR radio (XPR 4550), just not sure how to program it to monitor a Connect Plus system.

 

[Forts]

Oh! That part's easy. Make a zone for the system you want to monitor. Program each connect plus channel twice (one on TS1, the 2nd on TS2). Make a group list with the talkgroup(s) that you want to monitor and assign it to all the channels. Set all the channels to Auto Scan and put them all in a scanlist, assign scanlist to channels. Done and done!

 

[thrivestorm]

Is there a way to monitor all talkgroups but have the ID show up?

 

[Forts]

*all* talkgroups? No.... There isn't any way to do that unfortunately. The only groups you will hear are the ones in your RX group list.

 

[Forts]

Remember, the radio isn't supposed to work like a scanner. It's supposed to sit on one talkgroup and perhaps scan a few others, that's it. Thankfully we can even monitor Connect Plus passively like this. Doesn't work on similar systems like NexEdge.. Kenwood made sure that passive monitoring wouldn't work.

 

[thrivestorm]

Very true. Thanks.

 

[thrivestorm]

Alright that was way easier than I expected to program. Thanks for the advise. It appears to be working semi-decently. I guess you can't expect it to work that well without interpreting the control channel data.

Edit: Two Questions:
1) To improve picking up scanned channels rapidly I want to minimize the number of channels the radio is scanning. Is TimeSlot 1 of the control channel only for data and thus not worth scanning? What about TimeSlot 2?
2) I've noticed that all LUNS on Connect Plus channels are odd numbered, but the control channel refers to both odd and even numbered channels. Is TimeSlot 1 the odd numbered channel, but TimeSlot 2 the even numbered channel of the same LUN?

Thanks.

 

[thrivestorm]

And a third question...when I receive audio the Group Call Contact Name is displayed on the screen with what I am assuming is the unique radio ID above. I would like to still be able to see what channel is currently being used. Is there someway to do this or some option in the CPS? Thanks.

 

[Forts]

1 - the control channel is always TS1 on whatever frequency is being used. It can rotate to other channels so you have to be careful about leaving slots out. I used to leave out the slot that the CC was using but then realized I was missing traffic (when watching the system with DSD+).

2 - I have no idea what an LUN is, sorry. That's not something I've seen before related to DMR.

3 - yes, the radio ID is on the top line during a call. The radio will always show the active talkgroup during a transmission, not the channel name. You cannot override this.

 

[thrivestorm]

Ok, thanks. And sorry I mean LCN not LUN, mixed up trunked channels with iSCSI networking.