XPR 7550 Capacity Plus and Conventional DMR

[BlackSheepDue]

I will preface this post by saying I am predominantly an apx user so I am not as well versed in XPR's or DMR in general.

I bought a xpr7550 just to monitor the two towns near me that have gone DMR, Westbrook and Falmouth, Maine. I then discovered that a private ambulance in my area has a "Motorola Capacity Plus Multi Site" system so I figured out how to add that in. The only thing I can't figure out is how to scan both the conventional DMR channels of Westbrook and Falmouth as well as MEDCOMM's capacity plus system at the same time. Maybe this isn't possible but it seems no different to me than my apx8000 scanning conventional and P25 trunking at the same time.

 

[K2NEC]

Due to the nature of DMR trunking, this is not possible

 

[rad127]

The answer I always got was "you can't" but there is a way to monitor a trunked CAP+ and one or more stand alone DMR systems at the same time using an XPR7550. A different question is "what I should I use to do this?" and the answer to that would be a scanner, which may be cheaper than a 7550 but that's not what you asked. The following, while a bit klugey, is responsive to your question:

Note this works for a Cap+ site and the limit on a Cap+ Multi Site would be how many total frequency/slot combinations there are (see scan option below with limit of 16 entries). And this isn't a setup to transmit, just listen.

Set up a new zone under Channels with each Cap+ frequency, selecting "Digital Channel" rather than a "Cap+ personality", with one entry per repeater slot. So a 5 frequency system would have Freq1Slot1, Freq1Slot2, Freq2Slot1, etc.
Choose Rx only, and proper color code.
Add the DMR channels.
You need to have a group list set up under "RX Group List" > "Digital". Put all the Cap+ Talkgroups you want in this list.
Make additional group lists for the other DMR systems with their specific Talkgroups.
You need to have a scan list under "Scan". Put all the repeater freq/slot combos plus the individual DMR channels as "Members"
The hard limit here is you can only scan a max of 16 channels, so with 8 Cap+ frequencies x 2 slots you're already at 16.
Under each Cap+ Channels you created, you add the Group List from the dropdown in the RX section and the scan list under the Scan/Roam dropdown.
The standalone DMR channels should have the same scan list but a different Group List (since they have different TGs).
Add a button to enable/disable scan.

If you have too many frequencies with a multi-site I suppose you can set up different Zones with the different freqs for each area but if you're total combination is 16 or less this will work, although not the best and your mileage may vary. And since it's not a scanner there is the speed issue of going from channel to channel and there's not an easy way to cycle TGs in and out, other than making multiple zones with slight variations. If you want to transmit, you will need to delay a few seconds to switch to a different zone with the specific system set up properly

Also the cheapest of the CCRs that does DMR will likely let you add a lot more than 16 channels. Or use a scanner....

 

[tunnelmot]

Are you following the private ambulance system truly as a Cap Plus system (as an authorized affiliated subscriber)?, or simply scanning the system frequencies/timeslots for voice traffic(passively)?

I successfully scan analog, conventional DMR, and Cap Plus/Connect plus systems in one scan list and in one zone. BUT I'm scanning the trunked systems conventionally using talkgroup filtering. Works really well actually.

 

[BlackSheepDue]

Are you following the private ambulance system truly as a Cap Plus system (as an authorized affiliated subscriber)?, or simply scanning the system frequencies/timeslots for voice traffic(passively)?

I successfully scan analog, conventional DMR, and Cap Plus/Connect plus systems in one scan list and in one zone. BUT I'm scanning the trunked systems conventionally using talkgroup filtering. Works really well actually.

I set up the private ambulance as a capacity plus system but somewhere in the setup I was able to check 'receive only.' Although I can't remember exactly where in the process I was. I am not an authorized subscriber, just wanted to try monitoring something new.

Is the talkgroup filtering the same thing as what rad127 suggested?

 

[BlackSheepDue]

The answer I always got was "you can't" but there is a way to monitor a trunked CAP+ and one or more stand alone DMR systems at the same time using an XPR7550. A different question is "what I should I use to do this?" and the answer to that would be a scanner, which may be cheaper than a 7550 but that's not what you asked. The following, while a bit klugey, is responsive to your question:

Note this works for a Cap+ site and the limit on a Cap+ Multi Site would be how many total frequency/slot combinations there are (see scan option below with limit of 16 entries). And this isn't a setup to transmit, just listen.

Set up a new zone under Channels with each Cap+ frequency, selecting "Digital Channel" rather than a "Cap+ personality", with one entry per repeater slot. So a 5 frequency system would have Freq1Slot1, Freq1Slot2, Freq2Slot1, etc.
Choose Rx only, and proper color code.
Add the DMR channels.
You need to have a group list set up under "RX Group List" > "Digital". Put all the Cap+ Talkgroups you want in this list.
Make additional group lists for the other DMR systems with their specific Talkgroups.
You need to have a scan list under "Scan". Put all the repeater freq/slot combos plus the individual DMR channels as "Members"
The hard limit here is you can only scan a max of 16 channels, so with 8 Cap+ frequencies x 2 slots you're already at 16.
Under each Cap+ Channels you created, you add the Group List from the dropdown in the RX section and the scan list under the Scan/Roam dropdown.
The standalone DMR channels should have the same scan list but a different Group List (since they have different TGs).
Add a button to enable/disable scan.

Thank you for your detailed reply. I agree that using a scanner would be easier but unfortunately I have become a bit of a Motorola snob over the years. I don't mind the challenge either as long as it's possible and it seems to be with what you have laid out. I will have to give your process a try after work today. I have 6 DMR conventional channels in the scan list currently and the capacity plus system has 3 frequencies. That would put me at 12 total members in my scan list correct?

 

[IAmSixNine]

Basically all you are doing is dumbing it own to each frequency, color code time slot and talk group, then scanning those channels.
The busier cap plus or con plus system is the more likely you are to miss traffic. The radio will stop on an active channel looking for matching criteria, slot, cc and tg. Then it will scan to the next one.
With something like this it might be best to have 2 receivers. Use a scanner for connect plus and the conventional dmr channel and the 7550 for the cap plus stuff. Or mix and match till you figure out what works best for you.
But using your 7550 to monitor all of that at once is extremely inefficient and will result in missed conversations. The more you scan the more you miss.

 

[BlackSheepDue]

Basically all you are doing is dumbing it own to each frequency, color code time slot and talk group, then scanning those channels.
The busier cap plus or con plus system is the more likely you are to miss traffic. The radio will stop on an active channel looking for matching criteria, slot, cc and tg. Then it will scan to the next one.
With something like this it might be best to have 2 receivers. Use a scanner for connect plus and the conventional dmr channel and the 7550 for the cap plus stuff. Or mix and match till you figure out what works best for you.
But using your 7550 to monitor all of that at once is extremely inefficient and will result in missed conversations. The more you scan the more you miss.

What you're saying totally makes sense. The vast majority of the time my apx8000 is scanning vhf conventional and a busy 800 p25 trunking system and I know I miss stuff because it's just a lot for the radio to listen to. If I'm sitting at my computer or something I use a xts5000 for the busier trunking TG's to lighten the load of the 8000. From what monitoring I have done of this capacity plus system it's about as interesting as one might imagine a private ambulance to be. Mostly "en route, on scene, transporting, etc." and shuttle busses discussing Portland traffic. Ultimately I probably just won't monitor it as the fire and police departments using conventional DMR are far more interesting to me but I was curious as to what was possible.

 

[rad127]

That would put me at 12 total members in my scan list correct?

Yes, that would be 12 total members.
Also, when I said to put the talkgroups you want in the "RX Group List" > "Digital". I forgot to say to need to add those talkgroups first as "Contacts" > "Digital" .
If the Cap+ plus system was set up correctly for normal use those talkgroups would already be under "Contacts" > "Capacity Plus", but when you create the new Digital RX Group List you won't see Capacity Plus talkgroups. So you need to create the ones you want as Digital Contacts, putting the TG as "Call ID".

The RX Only is a check box on the digital channel, just above where you'd enter the RX & TX frequencies

 

[BlackSheepDue]

Yes, that would be 12 total members.
Also, when I said to put the talkgroups you want in the "RX Group List" > "Digital". I forgot to say to need to add those talkgroups first as "Contacts" > "Digital" .
If the Cap+ plus system was set up correctly for normal use those talkgroups would already be under "Contacts" > "Capacity Plus", but when you create the new Digital RX Group List you won't see Capacity Plus talkgroups. So you need to create the ones you want as Digital Contacts, putting the TG as "Call ID".

The RX Only is a check box on the digital channel, just above where you'd enter the RX & TX frequencies

I was successful in setting up your method so we'll see if I like it or not. Initially it seems like the radio will hang on one of the "capcity plus channels" for 5-10 seconds after a transmission which is doesn't do on the regular dmr channels or when I'm monitoring the capacity plus system properly.

 

[tunnelmot]

Keep us updated.

 

[BlackSheepDue]

Not much to update. I've used it for about 1 full day now. I took out one talkgroup because it was just shuttle busses and listening to it was driving me nuts. I still notice it hanging on a cap + TG for about 5 seconds after a transmission pretty much every time. Every once in awhile it seems like I'm missing transmissions on conventional dmr channels even when there hasn't been any cap + traffic but that's likely just me over analyzing or a weak signal.

 

[Forts]

Unfortunately this is a case where a scanner actually works better. I'm in the same boat at my work... we have a Capacity Plus system that carries the bulk of traffic, but also 3 conventional security and emergency channels. Trying to scan a mix of both is a real pain, but I've been doing it for a few years using the method described above. It's kind of kludgy but works fairly well. On a really busy system you will miss a little traffic here and there however.