DSDPlus DMR TIII non std network to be identified

[iu7dkq]

Hi Folks, scanning the UHF frequencies, I came across a DMR channel that shows the following:

2025/07/28 22:56:15 Freq=420.431250 Current network: H1
2025/07/28 22:56:15 Freq=420.431250 Current site: H1-106
2025/07/28 22:56:16 Freq=420.431250 DCC=0 RAS H1-106 neighbor: Site H1-67; CC=825
2025/07/28 22:56:16 Freq=420.431250 DCC=0 RAS H1-106 neighbor: Site H1-107; CC=837
2025/07/28 22:56:16 Freq=420.431250 DCC=0 RAS H1-106 neighbor: Site H1-74; CC=813
TIIInonSTD [Auto] Site:H1-106 DCC:0 RAS NL:67 74 107


2025/07/28 22:59:04 Freq=420.556250 Current site: H1-107
2025/07/28 22:59:04 Freq=420.556250 DCC=0 RAS H1-107 neighbor: Site H1-106; CC=817
2025/07/28 22:59:04 Freq=420.556250 DCC=0 RAS H1-107 neighbor: Site H1-67; CC=825
2025/07/28 22:59:04 Freq=420.556250 DCC=0 RAS H1-107 neighbor: Site H1-74; CC=813
2025/07/28 22:59:04 Freq=420.556250 DCC=0 RAS H1-107 neighbor: Site H1-91; CC=849
TIIInonSTD [Auto] Site:H1-107 DCC:0 RAS NL:67 74 91 106

the two sites appear to be neighbor to each other

Having only one sdrplay available it is possible to reconstruct the entire network and the related channels so as to be able to appropriately configure the DSD+ files to listen to their traffic?

Can you help me understand how to proceed?

 

[pro92b]

The data you provided identifies the control channel frequencies. If you sit on a control channel and log traffic then voice channels should be identified by LSN. Use the program in the attachment to identify frequencies.

 

[BM82557]

The data you provided identifies the control channel frequencies. If you sit on a control channel and log traffic then voice channels should be identified by LSN. Use the program in the attachment to identify frequencies.

View attachment 187682

Download link for the utility he posted about is contained in this thread --

LCN to Frequency calculator for DMR TIII

Seems like a few people are interested in this calculator I mentioned in a post a few days ago. Here it is. This is only for calculating LCNs for DMR TIII. It will not work for CAP+,CAP MAX, CON+ or any other system. This 'DMR_TIII_LCN_Freq_calc' is provided 'as is'. - This is just a basic...

forums.radioreference.com

 

[mtindor]

The data you provided identifies the control channel frequencies. If you sit on a control channel and log traffic then voice channels should be identified by LSN. Use the program in the attachment to identify frequencies.

View attachment 187682

Ok I'm back to being convinced it's using 12.5 KHz bandplan, not a 6.25 KHz bandplan.

For the op (and this is just to start out):

;DSDPlus.Networks
TIIInonStd, H1, "company name"

;DSDPlus.Sites
TIIInonStd, H1, 67, "Site 67"
TIIInonStd, H1, 74, "Site 74"
TIIInonStd, H1, 91, "Site 91"
TIIInonStd, H1, 106, "Site 106"
TIIInonStd, H1, 107, "Site 107"

;DSDPlus.frequencies
TIIInonStd, H1, 67, 825, 420.48125, 0.0, 0
TIIInonStd, H1, 74, 813, 420.40625, 0.0, 0
TIIInonStd, H1, 91, 849, 420.63125, 0.0, 0
TIIInonStd, H1, 106, 817, 420.43125, 0.0, 0
TIIInonStd, H1, 107, 837, 420.55625, 0.0, 0

You will then need to sit on one of the control channels (either the one for Site 106 or Site 107 that you can hear. You will have to wait for voice traffic to occur (private / group calls). And when those occur, your Channel Activity window will list additional Channel Numbers under the "ch" column in the Channel Activity Window. Once you note additional channel numbers in use, you can use the calculator (12.5 khz spacing) to figure out the frequencies for those additional channels.

Or if you are still confused by all of this, just make note of all group/private call channel numbers / LSNs and post here what you get. Then we can help you fill out the details more. But you may have to let it set on the Control Channel for a significant amount of time to wait for voice calls. No voice calls, no channel numbers/LSNs.

I have a feeling this is going to be a little bit awkward due to possible language barriers.

Ho la sensazione che la situazione sarà un po' imbarazzante a causa delle possibili barriere linguistiche.


Mike

 

[Muxlow]

Iv got a similar thing with a TIII nonstd system (capacity max)
Using the calculator im not getting any of the confirmed frequencies for a couple sites. They are way off no matter what i change the spacing to

Example
Site 34 6807 420.7375
Site 33 6607 420.15
Site 3 607 420.975
Site 2 413 420.900
Site 36 7205 420.325
Site 30 6003 Unknown
Site 1 213 420.4875

Cant get that lsn calculator to match up any of these or figure out what 6003 is. They should all be in the 420's and not 421/422's

 

[mtindor]

Iv got a similar thing with a TIII nonstd system (capacity max)
Using the calculator im not getting any of the confirmed frequencies for a couple sites. They are way off no matter what i change the spacing to

Example
Site 34 6807 420.7375
Site 33 6607 420.15
Site 3 607 420.975
Site 2 413 420.900
Site 36 7205 420.325
Site 30 6003 Unknown
Site 1 213 420.4875

Cant get that lsn calculator to match up any of these or figure out what 6003 is. They should all be in the 420's and not 421/422's

The maintainers can manually set a random LCN<-->Freq pairing if they want. It appears that they do that on the system you are referring to (Prairie). If you just look at the first three sites in the DB, if a person can assume that the details for the first three sites are correct, then clearly they are not using a specific bandplan systemwide. It might not be totally random, but they aren't using the same base frequency on each site. I know nothing about those sites or the people who have submitted data or where they've gotten that data. If all of the data was provided by DSDPlus or SDRTrunk I'd trust it. If it were determined by a Uniden LCN finder, I'd probably be skeptical myself. I do not trust the LCN Finder on DMR T3.

Anyway, the CAPMAX documentation, if one is privy to it, indicates [to me] that the LCN<-->freq pairing can be made up manually at the whim of the maintainer and doesn't actually have to adhere to any bandplan, per site or systemwide.

 

[DaveNF2G]

I doubt you'll see many "custom" bandplans in the real world. The people who install these systems are not generally that clever. I mean, if you can't replace CHANGEME as your system identifier...

 

[mwjones]

I doubt you'll see many "custom" bandplans in the real world. The people who install these systems are not generally that clever. I mean, if you can't replace CHANGEME as your system identifier...

In my travels I've found two that don't use a traditional Tier III bandplan - A Tait system operated by the Kansas City Area Transportation Authority, the other a VHF CapMAX for Cherokee Nation Healthcare in Northeast Oklahoma (WRKD729 and WRKD737 not in RRDB yet, as I don't go through that area enough and I don't know if others have been doing any discovery on it)

 

[Muxlow]

The maintainers can manually set a random LCN<-->Freq pairing if they want. It appears that they do that on the system you are referring to (Prairie). If you just look at the first three sites in the DB, if a person can assume that the details for the first three sites are correct, then clearly they are not using a specific bandplan systemwide. It might not be totally random, but they aren't using the same base frequency on each site. I know nothing about those sites or the people who have submitted data or where they've gotten that data. If all of the data was provided by DSDPlus or SDRTrunk I'd trust it. If it were determined by a Uniden LCN finder, I'd probably be skeptical myself. I do not trust the LCN Finder on DMR T3.

Anyway, the CAPMAX documentation, if one is privy to it, indicates [to me] that the LCN<-->freq pairing can be made up manually at the whim of the maintainer and doesn't actually have to adhere to any bandplan, per site or systemwide.

Iv submitted all the data for that system so far using DSD+ so id go with they are doing their own thing LCN wise. They currently have a connect plus system they are taking frequencies from and putting onto this system and at some point will be converting all their customers over to cap max

 

[iu7dkq]

I have a feeling this is going to be a little bit awkward due to possible language barriers.

I apologize, I don't understand much English, so I use Google Translate. However, I'm trying to understand what you're explaining here as best I can.

Thanks everyone for your help. I'll try listening on the CC channel to get more data.

 

[wonkaski]

Hytera Radios allows a "dynamic" band plan, which allows Tier III systems to have a customized bandplan and LCN. Which means they can have 420.0125 as LCN 1 then 420.250 as LCN 888, whatever they program the system and the radio.