DMR/MotoTRBO mode not working

[PhillyPhoto]

There's a DMR Tier 3 system near me and I'm trying to setup my 325 to work with it. I have 3 systems configured now.

• The first is conventional only and it shows me the frequency and color code and will decode audio with no issues.
• The second is a DMR 1-frequency system. It shows me the talkgroup and radio IDs when it stops on the individual frequencies.
• Finally, I also have a DMR/MotoTRBO system (after buying and configuring the DMR upgrade direct from Uniden). This one does absolutely nothing, ever.

I followed the instructions at the bottom of the DMR upgrade wiki to determine the LCNs from the LSNs showing up in DSD+ FastLane. Below is the system breakdown:

LSN     Freq        LCN
223     451.3750    111
224     451.3750    111
347     452.1500    173
348     452.1500    173
459     452.8500    229
460     452.8500    229
2165    463.5125    1082
2166    463.5125    1082

463.5125 is the control channel for the site so I've put what it should be based on the other channels, and the other frequencies are what DSD+ shows, and has no problem tracking the voice channels on my PC.

 

[PhillyPhoto]

Something that's confusing is @UPMan stating here:

To get the LCN for the channel, divide the higher LSN by 2 (i.e. if frequency has LSN 7/8, the LCN is 4).

Yet, on the Uniden site, it says:

DSD+ combines the LCN and Slot together in the style of MotoTRBO Capacity Plus. This combination was coined as LSN. You need to divide the lower number by two and ignore the fraction.

If you follow Paul's post, you'd get 112, 174, 230, 1083 for the LCNs. If you follow the website, you'd get 111, 173, 229, 1082 as the LCNs.

I've tried both, and neither have worked thus far.

 

[GMB951]

I have ran into a problem I had to reset my BCD 996P2 and now it will not decode DMR/NXDN in the service search mode but is doing fine on the DMR/NXDN systems I have in banks already

 

[simmsrep]

I have a similar system in a county to the east of me. Same setup as you have described, a DMR Tier 3 system with 5 sites. Each site has 4 frequencies. Using DSD+ the LCN's are (as you described on yours) ex. 460.0625 shows 1930. So I subtracted 2 then divided by 2 to get 964 to program in the scanner. Even with that the decoding is very sporadic. I can get the sheriff channels but it never stops on the fire or EMS. So I think you have your LCN's programmed correct. I have the 325, a 536 and a sds100. Out of the three the sds100 decodes this system the best but is still missing a lot of transmissions. The 536 would be second best but my 325 just doesn't do good at all. I think it has something with it being an RAS system also. I ended up just programming the site frequencies as conventional with digital only mode and it picks up great but it doesn't show what the talkgroups are (the 536 will). I think Uniden probably needs to tweak some on these systems.

 

[PhillyPhoto]

So, I'm thinking is a Hytera system based on the control channel window (attached) with "TIII (HYT)" as I have seen some as "(MOT)" for Motorola. It also doesn't so RAS, so I don't think it's that issue that others have reported when trying to monitor a T3 system.

@simmsrep something to try would be setting up a "one frequency" system. It's kind of a hybrid, and does do the trick as a stop gap for me. You program all the channels, and it will show you the talkgroup and unit ID. The only thing it doesn't do is actually track the system as a trunked system. It just looks for activity on the individual frequencies.

The only issue is that I paid $60 for it to track the actual trunked system. For the $85 that Scanner Master is charging for the DMR upgrade, you could buy a conventional DMR radio.

 

[GMB951]

Does anyone know what to do to recover NXDN/DMR reception on service search after doing a reset on a BCD 996P2

 

[KevinC]

Does anyone know what to do to recover NXDN/DMR reception on service search after doing a reset on a BCD 996P2

Under "Srch/CloCall Opt" go to "Tone/Code Search" and choose "P25/NAC Search".

 

[GMB951]

That worked thank you so very much

 

[PhillyPhoto]

I think my LSN/LCN for the control channel was wrong in the original post (highlighted in red in the table below). I ran a formula based on the LSN's showing up in DSD+ to figure out what the LSN should actually be for the control channel, and revised it.

I then looked at another DMR system. This one was a "Motorola Connect Plus (TRBO)" system, and I believe the one I'm trying to figure out is a Hytera. Fundamentally they should be pretty similar however since they're both DMR Tier 3, right? The LCN's that worked as listed in the DB did align with the info from Uniden's site (highest LSN/2). I then tried using the LCN's listed below with no luck.

DSD+ LSN	Frequency	Paul's method LCN	Uniden's Method LCN
223	451.37500	111	112
224	451.37500	111	112
347	452.15000	173	174
348	452.15000	173	174
459	452.85000	229	230
460	452.85000	229	230
3871	463.16250	1935	1936
3872	463.16250	1935	1936

One oddity I noticed was when I stopped on the Motorola system, the system & site matched DSD+. On the Hytera system, the numbers are 1 below what the 325 shows on the control channel. Running with that, I did try the LCN-1 method and stepped each frequency's LCN down 1 in the site, but still got nothing.

 

[W4KRR]

PhillyPhoto,

I also have a BCD325P2, and I have a similar issue.

A local Hytera Tier 3 system works just fine on this scanner, but a Motorola Capacity Max Tier 3 system will not stop on any active talkgroups or pass any audio. I had thought that maybe it was because the Motorola Capacity Max system in question uses RAS. However, this same system works on the Uniden SDS100.

Here is the method for determining the LCN's using the data you get from DSDPlus:

DSD+ combines the LCN and Slot together in the style of MotoTRBO Capacity Plus. This combination was coined as LSN. You need to divide the lower number by two and ignore the fraction.

1899/1900 would be 949
1941/1942 would be 970
1985/1986 would be 992

The formula above does work for use in the SDS100 and BCD436HP, but for some reason the BCD325P2 has trouble with this system, as in, it doesn't work at all. I have also tried different formulas, as you have, with no luck.

I wish Uniden would address this issue.

 

[PhillyPhoto]

@W4KRR what I don't understand is why are adding the LCNs even needed if DSD+ can take the input of the control channel and nothing else and figure it all out by itself? It should be just like a P25 system where all you need to enter are the control channels. $60/scanner to Uniden for something that doesn't work vs $25 for lifetime Fast Lane upgrades is a no brainer.

If I manually stop scanning and scroll between the frequencies in my site, I hear the traffic just fine. So clearly reception is not a factor. It just cannot figure out how to do anything with the data it's getting from the control channel sometimes I think.

I wouldn't even be where I am trying to figure this out if it wasn't for DSD+. The frequencies used in this system are under 4 different CC licenses. Granted, they are all owned by the same licensee at the same physical site, but still...

 

[wx5uif]

P25 transmits the band plan. DMR does not, so the scanner cannot know what frequency each LCN is.

 

[PhillyPhoto]

P25 transmits the band plan. DMR does not, so the scanner cannot know what frequency each LCN is.

Then DSD+ is doing magic. Literally all you need to do is tune to a DMR control channel and it finds and will tune a secondary dongle to the correct voice frequencies with no intervention on my part.

Before I had fast lane, I tried entering the channels (based on the FCC license the control channel is under), and got nothing. Once I upgraded, it figured it out on its own, even with my bad information.

Sent from my SM-G950U using Tapatalk

 

[W4KRR]

As far as DMR systems: DSD+ tells you the channel numbers that the system administrator has assigned. It does not tell you what frequency goes with each channel number, as they can and do vary from system to system. It depends on how the system administrator has assigned the frequencies to each channel number, usually through some sort of table, but not always.

And yes, if I monitor the individual frequencies on the Motorola capacity Max Tier 3 system, I hear calls loud and clear. But if I set the scanner up for trunking, it won't pass any audio or stop on any talkgroup.

 

[PhillyPhoto]

As far as DMR systems: DSD+ tells you the channel numbers that the system administrator has assigned. It does not tell you what frequency goes with each channel number, as they can and do vary from system to system. It depends on how the system administrator has assigned the frequencies to each channel number, usually through some sort of table, but not always.

Again, this is not true for what I have observed with DSD+ Fast Lane on 2 different computers. I think it may use a default base frequency of 450.000, and see if it detects the talkgroups on the calculated frequencies. Just like you can do with a default band plan on old Motorola systems. Or if it can detect what LSN the control channel is configured as, it can work backwards to determine the base frequency and go from there.

I tried to setup the system using the completely wrong frequencies, and when I upgraded it to the Fast Lane it instantly started working and found the correct ones on it's own. I understand that DMR T3 doesn't broadcast the band plan, but that doesn't detract from DSD+ is doing the calculations.

Here are the calculations for my system based on a default base frequency of 450.000 and a 12.5kHz spacing (using the even LSN for calculations):

LSN as reported by DSD+	Step (in MHz)	Difference (in MHz) ((LSN/2 time slots)*Step)	+ Base Frequency
224	0.0125	1.375	451.375
348	0.0125	2.15	452.150
460	0.0125	2.85	452.850

I then worked in reverse to determine the LSN for the control channel:

Control Channel	Difference (in MHz) (CC - Base Freq)	Step (in MHz)	LSN ((Difference / Step) * 2 time slots)
463.5125	13.5125	0.0125	2162

I've tried the LCNs (Even # LSN/2) on the BCD325P2, and have gone +/-2 and have not gotten it to stop on a talkgroup, let alone unmute.

 

[PhillyPhoto]

Here's a video of what the radio does:

The "1.4" is just the channels programmed as conventional. "Avon Test" is it programmed as "MotoTRBO" which doesn't work. Finally "Avon" is DMR one-freq which lets me see the talkgroups and does work.

 

[W4KRR]

If I run DSD+ Fastlane on a DMR system, it will only show channel numbers until I go into the DSDPlus.frequencies file and manually add each frequency next to the channel number. At that point DSD+ will start to track the system and provide audio, assuming I have entered the correct frequencies.

At least one DMR system around here uses some frequencies with channel numbers that are "out of order" from any table; there's no way DSD+ could know what frequencies are associated with a particular channel number in this case. I have not observed DSD+ automatically providing the frequencies on DMR or NXDN systems, only on P25 systems.

 

[PhillyPhoto]

I'm running Fast Lane v2.186, I'm not sure which version you have. But like I've said, I haven't entered any frequencies. It just finds them.

 

[PhillyPhoto]

@UnidenSupport any suggestions? Uniden | Portal has been less than useful so far to say the least.

 

[UnidenSupport]

We have a case about this that we have been kicking around, i'm not sure if that is from you. We are currently awaiting a response from tech and I should be able to update you when I hear back.