DSDPlus DSD+ FastLane with DMR T3

[rkillins]

I'm starting a journey to monitor a local DMR Tier 3 Standard. I looked through the DSD+ provided notes, specifically from update 2.457 and later, to try and get a handle of it. I'm really unsure if my file line formats are correct. The notes gave a few examples, but became quite confused over the "NetworkModel and ID"

I think I have a handle on the T3 standard format, the information is clear in RR. Consider this system:
T3 standard system: FastNet, site 3 Brisbane
Network File Entry:
TIIIStd LD "Coyote LLC"
Site File Entry:
TIIIStd LD 2.3 "Brisbane"
Where L13 is the system network mode an 2.3 represents the region.site.

There is one difference with a T3 nonstandard format that I can't figure out. DSD+ notes reflect this format for the network entry of a non-standard system:
TIIInonStd L1234:13 "Road Runner Inc" ; Protocol NetworkModel&ID NetworkAlias

I get that TIIInonStd is the protocol but what does the ":13" represent in the network model and ID?
I am trying to create a properly formatted network entry for this local local T3 nonstandard system : MRC Systems

I can only guess to this point:
TIIInonStd L6:xx "MRC Systems", where "xx" is a value I don't know how to determine or where to find (is in in the RR info somewhere?)

Then to follow up with a proper site entry, DSD+ notes indicate that the proper formatted site fiel entry is:
TIIInonstd L1234:13 1 "Home Base" ; Protocol NetworkModel&ID Area.Site SiteAlias
Is this a misrepresentation ... it says an area.site parameter. I only see a single 1 representing the area.site. In their example, was the area value omitted? Or is that what the "13" represents - the area. If it is the area (which I don't think it is. Ifit was there would need to be separate network lines for each area of the system), then that solves my "xx" question, and which makes the example in DSD+ notes a bit off. It should be
;Protocol NetworkModel&ID:area Site SiteAlias

So, my guesses for site:
TIIInonStd L6:xx 10 "Brisbane" where xx is not the area and in my case is a mystery and the format of area.site is incorrect in the example, or;
TIIInonStd L6:13 10 "Brisbane" where I make an assumption the 13 is the area/region, 10 is the site number and does not follow the region.site format of the example.

Once all of that is straightened out, I think I can manage the frequency information but not without some clarification on a couple things.
The notes share this example ...
TIIInonStd L1234:13 1 57 462.0125 0.0 0 ; Protocol NetworkModel&ID Area.Site Chan# ...
I deduce that TIIInonStd is the protocol, L1234:13 is the NetworkModel& ID, 1 is the site number, 57 the channel number, 462.0125 is a frequency, and the rest can be considered redundant information.
In my example ...
TIIInonStd, L6:xx, 10, 1053, 420.5875 0.0 0

Questions about T3 frequencies ...
I assume all frequencies of the site have to be entered. However, do all channel numbers have to be represented? Frequency 420.5875 is assigned to both channels 1053 and 1054. Does this also have to be included?

How does DSD+ handle missing frequency information? Since I haven't had a chance yet to monitor a T3 system with DSD+ I'm unfamiliar with what I can expect to experience. I assume that DSD+ can gather the channel numbers, but will not know their frequencies. Until those frequencies are figured out, there will be missed communications? How does one calculate the frequencies of channels? If system frequencies are found (either through TAFL or monitoring), how can one determine their channel numbers? It sounds like it could be a tedious endeavour.

Thanks in advance for your help, and I hope I presented my questions in a workable manner. I simply dumped the comments of my messed up understanding into words best I could, so I appreciate your patience.

 

[cg]

the L is the system Model size as specified in the DMR Standard. The 13 is the System ID. There is a default in the programming of the system where, unless it is changed, it will be 13.
Now, with a bunch of systems numbered L13, you need a way to tell them apart. So DSDPlus allows a extension to the System ID to separate similarly numbered systems called pseudo network ID. That is what the 1234 is for in the System ID you are referencing. Some folks use the Radio Reference system number assigned to that system to keep things separate.

 

[rkillins]

Thanks @cg. So, in the case of the TIIInonSTD system I'm trying to listen to, it has a system ID of L6. Does that mean I don't need the pseudo network ID? So, we'd be accepting ...

TIIInonnonStd, L6, "MRC Systems" ?

For the site, I notices that there are no region/area number associated to this site (a difference between standard and nonstandard TIII systems?), so my guess changes then to:
TIIInonStd, L6, 10, "Brisbane" ? (no area reference)

I put the T3 standard network line in my network's file
TIIIStd, LD, "FastNet (MRC T3Std)"
but DSD+ is reporting an error with it ... "invalid or missing network ID."
I think it's because I used the HEX value of the system ID (LD) vs the DEC value (L13). The decimal being L13, I guess this is where I need to use the pseudo ID?

TIIIStd, L10380:13, "FastNet" ?

I did this, and am still getting that error.

 

[mtindor]

LD Is not valid. you need to the decimal value of the network ID, not the Hex value.

TIIINonStd, L13, "FastNet"
TIIINonStd, L10380:13, "FastNet"

HOWEVER, the DB says it is DMR TIII Standard. It either is or it isn't. You need to figure it out first. The DB may not be right.

Just run DSDPlus Fast Lane without any sort of network/site/frequencie files related to Fastnet.

Park on a FastNet control channel that is strong and reliable and see what DSDPlus says

It's either going to say TIIIStd or TIIInonStd. It may also indicate if it is Motorola (Moto) or Hytera or Tait. But ti will indicate whether the system is TIII Standard or TIII nonstandard. After you know for sure what it is, and that the database is correct, then move forward with programming.

 

[mwjones]

I think it's because I used the HEX value of the system ID (LD) vs the DEC value (L13). The decimal being L13, I guess this is where I need to use the pseudo ID?

TIIIStd, L10380:13, "FastNet" ?

I did this, and am still getting that error.

The pseudo-ID has to be in the range of 0 - 4096, and that is likely what's causing the error. If this is the only Tier 3 system you're monitoring, then you don't really need to worry about the pseudo-ID. I have quite a few systems, most with network ID of 1 or 13, so I do use it.

 

[cg]

if you don't have another system with L13, you do not need the additional numbers in the ID, simply use L13. It is only used to keep the radios and groups separate for duplicate system IDs.

 

[rkillins]

Thanks folks for all your help, it's so appreciated.

HOWEVER, the DB says it is DMR TIII Standard. It either is or it isn't. You need to figure it out first. The DB may not be right.

Yes, I just assumed standard because RR made that claim, I'm assuming based on other's successes. The other system, MRC Systems (L6), I monitor is non standard. When I run DSD+ on that system, DSD+ plus confirms that with the "TIIInonStd (auto)" tag.

Park on a FastNet control channel that is strong and reliable and see what DSDPlus says

Unfortunately I haven't found a control channel to monitor. Of the 3 frequencies listed (1 "confirmed" CC) for the FastNet site I'm trying to monitor aren't active. Not sure if it's a reception limitation, or there are other unID'd sites out there to be found. The government database does not support that claim though.

The pseudo-ID has to be in the range of 0 - 4096, and that is likely what's causing the error. If this is the only Tier 3 system you're monitoring, then you don't really need to worry about the pseudo-ID.

I did not know this, that there was a limit, this is why I needed to come to you guys for help. I was grateful for the suggestion that @cg made in post 2 tand applied the SID value from the end of the the RR url from that system. It's redundant though, and I will remove that reference from my configuration, as it is the only L13 (so far) in my area. After having removed it, the error obviously disappeared.

So, now my network file, as the foundation for enties in site and frequencies, holds these lines for the two T3 systems I'm out to investigate:

TIIInonStd, L6, "MRC Systems (T3NStd)"
TIIIStd, L13, "FastNet (MRC T3Std)"

So, switching gears. The FastNet System isn't monitorable right now (I thought perhaps it was because of misconfigured DSD+ info), so with the MRC System (Nonstandard L6) I am able to pick up the control channel ont he closest ite - site 2 on 420.7500. am seeing active decoding. Mostly just registration entries, I'm not sure how much activity is on this system and if any if it'll be monitorable. Most of the talkgroups are from out of county and likely not routinely carried on my closest towers. The towers that would carry them are likely beyond range. My goal is to see how this system evolves locally, but I need to be able first to be able to monitor it.

Anyone have a moment to help me out with some frequency related questions?

I assume all frequencies of a site have to be entered. However, do all channel numbers have to be represented? Frequency 420.7500 is assigned to both channels 1079 and 1080. Do/should both channels have to be included for this frequency? For testing, I did include all channels in my frequency file.

How does DSD+ handle missing frequency information? Since I haven't had a chance yet to monitor a T3 system with DSD+ I'm unfamiliar with what I can expect to experience. I assume that DSD+ can gather the channel numbers, but will not know their frequencies. Until those frequencies are figured out, there will be missed communications? How does one calculate the frequencies of channels? If system frequencies are found (either through TAFL or monitoring), how can one determine their channel numbers? It sounds like it could be a tedious endeavour.

DSD+ Channel Activity Window is currently displaying ...

CH	TX Freq	Pri	Target	TgtAlias	Source	SrcAlias
1096
?	CC

Something must have been transmitted on channel 1096. The channel number is persistent. Does the associated frequency populate only when active? How come the CC channel number isn't revealed?

Any advice for happy and meaningful monitoring of T3 systems?

 

[cg]

the pairs of channels represent the slots assigned to each frequency (slot 0 and 1 but also commonly called 1 and 2). Only one needs to be populated in the .FREQUENCIES file.

Assuming the info in the database is open to non-premium subscribers, click on the Site name for frequency/channel info. (If you were a Premium Member, you could download DSDPlus formatted file entries)

For best experience with DSDPlus, learn to search the website here for answers, lots of issues with various setups have already been solved. Also, in you DSDPlus folder, there is a text file called Notes. This is where the improvements and changes are logged and often explained. It is a good reference using search in that file.

 

[mwjones]

Thanks folks for all your help, it's so appreciated.

We all had to learn this once, that's why there's so many here willing to help.

Yes, I just assumed standard because RR made that claim, I'm assuming based on other's successes. The other system, MRC Systems (L6), I monitor is non standard. When I run DSD+ on that system, DSD+ plus confirms that with the "TIIInonStd (auto)" tag.

I have found lots of systems in the RRDB that are incorrectly labeled. Just like you may see a system come up "TIIInonStd (MOT) (auto)" tag - that is a Motorola Capacity Max, which is Motorola's flavor of a T3 system - and is so common that you'll actually see that is a system type in the RRDB.

Unfortunately I haven't found a control channel to monitor. Of the 3 frequencies listed (1 "confirmed" CC) for the FastNet site I'm trying to monitor aren't active. Not sure if it's a reception limitation, or there are other unID'd sites out there to be found. The government database does not support that claim though.

I'm not sure about how it works in Ontario/Canada for licensing, but here in the US there's a segment of our UHF band that used to be reserved nationwide for pagers - some system operators have got permission to operate in that segment, and won't show in the license database. For those times, I break out the "survey" function of DSDPlus to get a "waterfall" of the entire band, and a strong control channel will show up clearly.

I did not know this, that there was a limit, this is why I needed to come to you guys for help. I was grateful for the suggestion that @cg made in post 2 tand applied the SID value from the end of the the RR url from that system. It's redundant though, and I will remove that reference from my configuration, as it is the only L13 (so far) in my area. After having removed it, the error obviously disappeared.

It is a bit confusing - Capacity+ and XPT systems support Pseudo-ID's of 0-65535, while T3 only supports 0-4096 - For Capacity+ and XPT, I clearly use the SID value, but for T3, I just use the last three digits of the SID value, as the chances of two systems that I'll monitor having the same last three digits is slim (and when I travel out of my region I start with a clean set of files so my primary files don't get bloated with stuff from places I may only visit once).

I assume all frequencies of a site have to be entered. However, do all channel numbers have to be represented? Frequency 420.7500 is assigned to both channels 1079 and 1080. Do/should both channels have to be included for this frequency? For testing, I did include all channels in my frequency file.

In your DSDPlus.frequencies file, you would only need to enter the entry once, with the channel (or more correctly, Logical Slot Number "LSN") for the lower of the two, which will always be the odd number - DSDPlus can extrapolate the even number entry without it being in the file.

For your frequencies that you don't know the LSN's for, enter a question mark "?" for the value, that way DSDPlus can search against it, but won't get the correct LSN for audio.

How does DSD+ handle missing frequency information? Since I haven't had a chance yet to monitor a T3 system with DSD+ I'm unfamiliar with what I can expect to experience. I assume that DSD+ can gather the channel numbers, but will not know their frequencies. Until those frequencies are figured out, there will be missed communications? How does one calculate the frequencies of channels? If system frequencies are found (either through TAFL or monitoring), how can one determine their channel numbers? It sounds like it could be a tedious endeavour.

DSD+ Channel Activity Window is currently displaying ...

CH	TX Freq	Pri	Target	TgtAlias	Source	SrcAlias
1096
?	CC

Something must have been transmitted on channel 1096. The channel number is persistent. Does the associated frequency populate only when active? How come the CC channel number isn't revealed?

T3 systems transmit their Channel or LSN over the air, and that translates to a "Bandplan" - once you know the bandplan, it's down to somewhat simple math to calculate the frequency. Keep in mind it's not a foolproof method, since some systems don't use a bandplan.

In the case of MRC Systems, site 2, there's already the LSN's discovered (and you can find that on the site page):



Using those two frequencies, I could calculate the base bandplan, and pretty much get the LSN for any other frequency. There are some free LSN calculators available here in the forum to save you the math, but a simple spreadsheet can do the work as well.

In this case we know 1079 is 420.75 and 1095 is 420.85. Plugging it in a calculator, LSN 1 (the "base frequency") is 414.0125, and the LSN increments at 12.5KHz steps - so 1081 (if that was actually in use on this site) would be 420.7625.

Your display currently says it doesn't know what LSN the control channel is using (the CH being ? next to the CC), but it is one of the two slots on 420.75. Once a transmission is received on the other timeslot on the same frequency, it will populate the CH correctly. Likewise a data transmission or some other "in band" communication was on Slot 2 of 420.850, so it will show but without the frequency, since you haven't defined it yet in the DSDPlus.frequencies file - once you edit that file and save it, the screen will reload but the next time a transmission is received, it will show (and if all goes well you should get audio).

Hope this helps.

 

[rkillins]

@mwjones, thank you for sharing such a detailed explanation. Very helpful. I'm all set up now to monitor.

 

[rkillins]

Hi Folks, thought I would update on my progress now that I have had some success decoding this local T3 system.
I have a two RTL-SDR dongle system. One monitors the control channel via FMP24, and the second follows the voice channels, via FMP24.Two instances of DSD+ running, the CC one assigned as 'CC Monitor' and 'Voice/Data call forwarding is checked. The event log window acknolwedges groups calls, and the CC Channel activity window populates with the channel number, TX Freq, target and source information when a group call is initiated.

But I am not hearing any audio from the voice side of things. The VC Event Log window populates accordingly when a group call is recognized, however, there is no activity in the VC Channel activity window when a call is active. DSD+ is set to VC Monitor, output to my speakers, synthesize all digital voice, and all protocols set for decoding are set. I am getting NoCCH and NoVF in my VC Event log window header.

Am I missing a setting?

 

[mtindor]

Hi Folks, thought I would update on my progress now that I have had some success decoding this local T3 system.
I have a two RTL-SDR dongle system. One monitors the control channel via FMP24, and the second follows the voice channels, via FMP24.Two instances of DSD+ running, the CC one assigned as 'CC Monitor' and 'Voice/Data call forwarding is checked. The event log window acknolwedges groups calls, and the CC Channel activity window populates with the channel number, TX Freq, target and source information when a group call is initiated.

But I am not hearing any audio from the voice side of things. The VC Event Log window populates accordingly when a group call is recognized, however, there is no activity in the VC Channel activity window when a call is active. DSD+ is set to VC Monitor, output to my speakers, synthesize all digital voice, and all protocols set for decoding are set. I am getting NoCCH and NoVF in my VC Event log window header.

Am I missing a setting?

Are you sure they groups are not encrypted? Encrypted groups are italicized.

Are you running FMP24-CC.bat, CC.bat and FMP24-VC.bat, VC.bat ? If you are running two dongles, those are what you should be running.

You should always try with one dongle, FMP24-CC.bat and 1R.bat first, with Combined CC/VC monitoring. Once you know things are working, then graduate to two dongles.

Screenshots of your DSDPlus Event Window and Channel Activity Window for each instance would be helpful as well.

 

[rkillins]

The last time I experienced this phenomenon I gave up and shut down the computer for the day, then returned the next day to play with it again only to find it was working. I should have remembered that before I wasted our time. A reboot was all that was needed apparently.
But thanks for your help, it's nice knowing it's there.
I looked through the DSD+ notes and did a Google search for NoVF. Notes simply said what it was, and it makes sense, but couldn't find any info on what causes it or what to do to resolve it. NoCCH means control channel hunting is disabled, which is appropriate, and it can be switched through the menus to turn t on.

 

[dave3825]

I looked through the DSD+ notes and did a Google search for NoVF. Notes simply said what it was, and it makes sense, but couldn't find any info on what causes it or what to do to resolve it.

Do you have Voice/Data Call Following checked?





Not saying its your problem but know if its not checked it will display NoVF in top of DSDPlus.

 

[rkillins]

Not saying its your problem but know if its not checked it will display NoVF in top of DSDPlus.

Yes, it is checked. It's actually checked and disabled (greyed out in the menu), I can't uncheck it if I wanted to. Its not there anymore, it disappeared, so something sorted itself out. Would it show up if the system were to reference a frequency not identified in the frequency file. I feel I may have an un identifed frequency on this site (a new channel number popped up not identified in RR).

 

[dave3825]

Are you running dual dongles or single dongles? What mode is it in?

I feel I may have an un identifed frequency on this site (a new channel number popped up not identified in RR).

Have a look in your other thread