SDR# TETRA Demodulator Trunk Tracking Demonstration

[hamradionl]

hornet1
For tetra i use only RTLSDR-V3, but still not able to tune PPM exactly to get zero beat on the frequency, therefor in left Radio menu change freq steps 6.25 to 1KHz.
The new TSSDR his plugin use auto tune AFC that helps and i have middle around 0.24 Hz freq drift. But the LowCost RTLSDR seem keep frequency drifting the whole time ( temperature )

 

[intruso]

Assuming these are group calls and priorities are ON.
If a call is in TS2 and TTT has set it up and is listening to it, then activity in TS3 should not be heard.
The only reason TTT would switch to TS3 (assuming D_Setup was detected) is because that the call in TS3 (GSSI) has a higher priority value.

It sounds like "Auto" checkbox is enabled.
"Auto" should be "OFF" or Unchecked. This should be disabled by TTT on "Start".


How priorities work with TTT,example:
GSSI: 1234 with priority value of 2
GSSI: 4321 with priority value of 6

Call is current with GSSI: 1234 and all is good in the world.
A "D_Setup" PDU is seen for GSSI: 4321.
Because GSSI: 4321 as higher priority (6) and obviously 6 is greater than 2.
TTT will then release call (GSSI: 1234) then setup the call for GSSI:4321.

And for the use of (call state)/priority snd file with TTT: (from "TTT_Features_and_Usage.pdf")
Only use one priority# WAV file at a time.
If more then one WAV file is used, only the highest number (file name #) will be in effect.

e.g. If snd_priority4.wav and snd_priority5.wav are seen by TTT then only snd_priority5.wav will be used.

When 'snd_priority5.wav' is used, GSSIs with a priority value of 5 and above will play that sound when a priority is triggered.
GSSIs with priority values of 1 to 4 will NOT play any sound when those priorities are triggered.

Well thewraith2008.

Thank you very much for your time answering.

No priority was established, all 0, now I will establish priorities.

Great job, I can not stop using TTT, now all the group and some ids have their label and in one color on the remote.
I can only speak well of this program

73 !!

 

[intruso]

hornet1
For tetra i use only RTLSDR-V3, but still not able to tune PPM exactly to get zero beat on the frequency, therefor in left Radio menu change freq steps 6.25 to 1KHz.
The new TSSDR his plugin use auto tune AFC that helps and i have middle around 0.24 Hz freq drift. But the LowCost RTLSDR seem keep frequency drifting the whole time ( temperature )

Without wanting to do an off-topic

In my case I use several dongles and I have to say that the tcxo and metal box, Frequency of compensation by -1 or -2.
In plastic dongles the compensation frequency goes up to +68.
I have to say in their favor that they hold their own ... I have had more than 12 hours and continue in conditions.

That's why I share this image that I saw looking for Ads-b and the stabilization of frequency and temperature.
It's an idea and apparently it works.

73

 

[Kenzi]

Hello after the last hotfix do you still need to feed the raw IQ from sdrsharp fileplayer to listen DMO?, or just tune to the right frequency use WFM activate DMO and listen?

 

[hamradionl]

intruso,
Good idea thanks sharing because for tetra the PPM stablity seem very importand
When you use the latest TSSDR release, he made a AFC and works great and wish AFC also for TTT

 

[Ubbe]

hornet1
For tetra i use only RTLSDR-V3, but still not able to tune PPM exactly to get zero beat on the frequency

I use RTLSDR V1 and can set the receive frequency +/- 1,5KHz off and still receive the signal. At +/- 1,8KHz it drops off. The frequency correction are set in ppm steps in the cog wheel settings in SDR# and one step is 400Hz at a 400MHz frequency. You should be able to set it 3 steps wrong, or drift 3 steps, and still receive a tetra signal.

/Ubbe

 

[hamradionl]

There must be a reason TSSDR made the AFC ON/OFF functionality.

 

[oz1jua]

Your original samples where a big help. Glad it works for you well.
At the moment I will focus on getting DM-MS to DM-MS working at little better. Do radios refer to this as "Direct". What is the feature terminology used by the manufactures?

It would be good if you could create a IQ sample for "Direct" on the 'B' channel.

Adding any features for something that is barely implemented is a bit premature at the moment.
That said, what do you mean "Scan of DMO". Is that scanning a list of frequencies that DMO traffic appears on?



In addition to this, DMO will only work on the current version of the plug-in if MNC is lower than 16383 (0-16382) because of the error described above.

Many thanks again. I have used this software for many days. And it is still super super.

I will try to make a sample where 2 radio talk to each other. Then it is more likely that you can see what is going on.
DM-MS Direct Mode MS (DM-MS) is the basic DMO model where 2 mobiles communicate over the DM air interface.
A DM-MS that initiates a call provides the air interface synchronization reference and becomes the master DM-MS.

I am not sure that I can make a sample for "Direct" on the 'B' channel.
I have only seen one radio that can do this, and this is EADS THR880i
But I did not found out what this was. It could be something that uses other time slot on same channel.
But I do not know for sure. But this radio play a sound that says A or B when switch on the wheel back on the radio.
I have not found any thing similar in a Motorola Tetra radio.

And Yes SCAN DMO Is scanning a list of frequencies that DMO traffic appears on?
Maybe one can find a plugin for this to use with SDRSharp

 

[thewraith2008]

hornet1
For tetra i use only RTLSDR-V3, but still not able to tune PPM exactly to get zero beat on the frequency, therefor in left Radio menu change freq steps 6.25 to 1KHz.
The new TSSDR his plugin use auto tune AFC that helps and i have middle around 0.24 Hz freq drift. But the LowCost RTLSDR seem keep frequency drifting the whole time ( temperature )

This option only serves to adjust the step size (up/down) when you use the wheel of your mouse to change frequency. This not any sort of frequency correction.

Hello after the last hotfix do you still need to feed the raw IQ from sdrsharp fileplayer to listen DMO?, or just tune to the right frequency use WFM activate DMO and listen?

Just use it as you normally would. The use of the "File player" plug-in is to play back IQ samples the helpful users supplied to me because I don't receive DMO broadcast in my location.

Yes use WFM, although you can use NFM (after starting "Demodulator"). Only tested with TMO not DMO.

Many thanks again. I have used this software for many days. And it is still super super.

I will try to make a sample where 2 radio talk to each other. Then it is more likely that you can see what is going on.
DM-MS Direct Mode MS (DM-MS) is the basic DMO model where 2 mobiles communicate over the DM air interface.
A DM-MS that initiates a call provides the air interface synchronization reference and becomes the master DM-MS.

I am not sure that I can make a sample for "Direct" on the 'B' channel.
I have only seen one radio that can do this, and this is EADS THR880i
But I did not found out what this was. It could be something that uses other time slot on same channel.
But I do not know for sure. But this radio play a sound that says A or B when switch on the wheel back on the radio.
I have not found any thing similar in a Motorola Tetra radio.

And Yes SCAN DMO Is scanning a list of frequencies that DMO traffic appears on?
Maybe one can find a plugin for this to use with SDRSharp

For DMO A/B channels I think maybe just a suggested feature the standard mentioned, but no manufactures implemented. (except the one you mentioned).

Just a general note to everyone that DM-GATE and DM-REP/DM-GATE are not supported by plug-in and will crash plug-in if seen.
I should release a hot-fix just to stop this crash sometime.

AFC that TSSDR has implemented recently may not work well with the frequency changing (following traffic) all the time.
It updates about once a second and only alters frequency if beyond a certain threshold.

 

[hornet1]

thewraith2008
Thanks I will be using the sdr# freq shift and test it.

I am getting lots of plain+encrypted traffic.
can can't wait to analyse them

 

[tsapers]

Anyone found that when running SDR# + TTT for some time (12+hours) SDR# hangs. Mostly see it on the VC instance, but sure I have had the same on CC instance and sometimes on both. Sometimes the Diagram in SDR# in the demod tab freezes and other times you can see that the VC doesn't jump to another carrier. I was on version 1660, now on 1700, but still the same happens. Only option is End Task via Task Manager.

Those running for days, what is your SDR# version and what active windows do you have open on Desktop? OS version?

 

[hamradionl]

and other times you can see that the VC doesn't jump to another carrier. I was on version 1660, now on 1700, but still the same happens. Only option is End Task via Task Manager.

TTT 1.05 /1.06 Running SDR# 1666
TTT 1.08 /1.09 Running SDR# 1700 this one i had same crashes like you discribe, did you install the newer HotFix ?
VC not jump, i notice this on busy traffic

 

[tsapers]

TTT 1.05 /1.06 Running SDR# 1666
TTT 1.08 /1.09 Running SDR# 1700 this one i had same crashes like you discribe, did you install the newer HotFix ?
VC not jump, i notice this on busy traffic

Thanks for the reply hamradionl

Was not aware of the HotFix. Checked airspy.com but could not see it?
Dont think it is due to the fact the the network is busy, the VC instance just becomes unresponsive, meaning it doesn't jump at all, but can see in TTT log the CC is still working as expected. Currently still running cheap blue dongles, awaiting delivery of V3's and wondering if the cheap dongle drifting isn't causing this.

 

[thewraith2008]

Thanks for the reply hamradionl

Was not aware of the HotFix. Checked airspy.com but could not see it?
Dont think it is due to the fact the the network is busy, the VC instance just becomes unresponsive, meaning it doesn't jump at all, but can see in TTT log the CC is still working as expected. Currently still running cheap blue dongles, awaiting delivery of V3's and wondering if the cheap dongle drifting isn't causing this.

He means the hot-fix for TTT and the plug-in
Release post (Hot-fix #2 - removed)
Re-release post (Hot-fix #3)

I'm sure I only added a cleanup of tabs "Call" for PDU log panel, "burst type" and "MS registrations" in last hot-fix #3. Maybe it's the one I've still not released?
This may have been cause if it was an out of memory condition. In task manager was the memory value a lot higher that 65-70Mb?
Now after about 1000 lines, these tabs are cleared.

EDIT: Also these tabs (with exception of 'Calls') are only updated when they are shown.
EDIT 2: In the TTT folder is a file "error.txt". Do any of the entries in the file match up in time to SDR# not changing frequency.
Sometimes the winsock (Net Remote plug-in) just jams up when it tries to receive 2 commands at once. (Because 1st one is delayed)
This happens so infrequently that I have not bothered to try and find out what causes it.

 

[tsapers]

He means the hot-fix for TTT and the plug-in
Release post (Hot-fix #2 - removed)
Re-release post (Hot-fix #3)

Apologies, though he was referring to SDR#. I am currently running TTT v1.0.7. I started a clean copy to see if it was caused by any update. My 1st step was to upgrade SDR# and now will also update TTT + hotfix to see if that works.

I have cleared the error and crash files (old entries) and will monitor these going forward.

 

[thewraith2008]

Hot-fix #4 for TTT v1.0.8 Public Release - Only updates TETRA Demodulator plug-in to v1.0.10


This hot-fix #4 is only for the full release version of TTT v1.0.8 and no other version.

TTT v1.0.8 (or the previous hot-fix #3) Must be installed first.


Only these two files have been updated:

• libtetradec.dll
• SDRSharp.Tetra.dll

Copy them to the usual places.





This plug-in version changes/adds and fixes some items:

v1.0.10.0

UPDATE: Implemented TSSDR code that improves demodulator. [Thank you TSSDR]
UPDATE: Implemented TSSDR code that adds - AFC.
UPDATE: Implemented TSSDR code that better handles PDUs in the MAC layer.
        - Gets remaining PDUs that where in MAC_resource.
        - MAC_resource fragmentation.

MOVED: DMO mode enable checkbox is now on main SDR# side panel, When ON, label text shows green.

CHANGED: Unallocated channel detection threshold. TESING: Increased from 3 to 5 timeslot.
         Some calls just abruptly end. I think this may just mean call has left LA.?
         I can't see any indication of why this occurs or is to about to occur.

ADDED: More elements to D_TX_Interrupt PDU (Testing)
 
CHANGED: More tweaking with handling of frame stealing and audio.

FIXED: DMO mode crash when DM-GATE or DM-REP/DM-GATE (i.e. unsupported) signals where seen.

CHANGED: DMO code tweaking.

CHANGED: Side panel UI - Slightly moved ISSI value to the left. Large values where crossing the panel
         boarder


MD5 HASH: b9f3173cb6e7dbecd35eecb831325b26 for "libtetradec.dll"
MD5 HASH: 1203363b450088ada5063da752da2b59 for "SDRSharp.Tetra.dll"

This updates some of the good stuff TSSDR has recently included.

A little more tweaking to the DMO workings here. Hopefully usable.
Still the DMO code is in it's early stage, it's implementation may not be 100% as expected.


NOTE: This will probably be the last release of the plug-in by me (Barring some major bug).
I wish to let TSSDR move forward with developing HIS plug-in the way he wants too.

Download link


MD5 HASH 8d6c2bce59b044dd74ec4f926cd22198

 

[thewraith2008]

Just a note to people trying out TSSDR's new release plug-in which he has starting implementing DMO.
Don't use it with AFC enabled, it doesn't work well with it turn ON.
On the version here, I've made it turn AFC OFF when DMO is selected.

 

[R3Natas]

Hi,
Testing your plugin right now, works better that before:
For DMO it works OK, but previous release was better, because now when transmitting it jumps between Slots, not very much, but it happens, reported to TSSDR as well (I haven't seen this "jumping" in the previous release).
For TMO it's awesome, AFC and other features have improved the plugin and I think my problem with "false ISSI" has gone, so it's a progress.
Thanks!

 

[hamradionl]

Very nice to see there is a cooperation between the two "gods" of tetra.
Thank you both for there efforts
thewraith2008, wish you be stay around and fallow.

 

[DarkAngelT]

Hot-fix #4 for TTT v1.0.8 Public Release - Only updates TETRA Demodulator plug-in to v1.0.10


This hot-fix #4 is only for the full release version of TTT v1.0.8 and no other version.

TTT v1.0.8 (or the previous hot-fix #3) Must be installed first.


Only these two files have been updated:

• libtetradec.dll
• SDRSharp.Tetra.dll

Copy them to the usual places.





This plug-in version changes/adds and fixes some items:

v1.0.10.0

UPDATE: Implemented TSSDR code that improves demodulator. [Thank you TSSDR]
UPDATE: Implemented TSSDR code that adds - AFC.
UPDATE: Implemented TSSDR code that better handles PDUs in the MAC layer.
        - Gets remaining PDUs that where in MAC_resource.
        - MAC_resource fragmentation.

MOVED: DMO mode enable checkbox is now on main SDR# side panel, When ON, label text shows green.

CHANGED: Unallocated channel detection threshold. TESING: Increased from 3 to 5 timeslot.
         Some calls just abruptly end. I think this may just mean call has left LA.?
         I can't see any indication of why this occurs or is to about to occur.

ADDED: More elements to D_TX_Interrupt PDU (Testing)

CHANGED: More tweaking with handling of frame stealing and audio.

FIXED: DMO mode crash when DM-GATE or DM-REP/DM-GATE (i.e. unsupported) signals where seen.

CHANGED: DMO code tweaking.

CHANGED: Side panel UI - Slightly moved ISSI value to the left. Large values where crossing the panel
         boarder


MD5 HASH: b9f3173cb6e7dbecd35eecb831325b26 for "libtetradec.dll"
MD5 HASH: 1203363b450088ada5063da752da2b59 for "SDRSharp.Tetra.dll"

This updates some of the good stuff TSSDR has recently included.

A little more tweaking to the DMO workings here. Hopefully usable.
Still the DMO code is in it's early stage, it's implementation may not be 100% as expected.


NOTE: This will probably be the last release of the plug-in by me (Barring some major bug).
I wish to let TSSDR move forward with developing HIS plug-in the way he wants too.

Download link


MD5 HASH 8d6c2bce59b044dd74ec4f926cd22198

Very good friend! Congratulations on the launch!
Apparently it's working very well! On tests here! Thank you to TSSDR !!!