DragonOS Focal Tetra Kit + Tetra Kit Player Usage (SigDigger, GNU Radio, HackRF, RTLSDR) 

I don’t have as much time as I once did, but when I get a chance to nerd out I figure I might as well record! Haha

So in this example the packets are being captured and decoded as they’re captured, the raw part you see being spit out is the audio which can be played as it’s being created with tetra kit player. I don’t really know of advantages or disadvantages, other then to say I guess this is providing a solution in Linux. I think nearly accomplishing the same thing as SDR+ (?) with some additional work. Probably a good educational tool to get someone using various different pieces of DragonOS to accomplish something? I dunno I just love needing out and using all sorts of things combined together haha! No problem on the work, it’s rather enjoyable.

I was initially asked to mute the audio but later provided more IQ files where I could’ve played the audio, I just didn’t have time. So what you see happening here is a representation of what would be happening in a real tetra environment. Ignore the fact I was playing back the captured IQ file, I was only doing that because I have no tetra to being with. So ignore the hackrf part and me opening IQ files and SigDigger, just imagine opening the rtlsdr flow graph, tetra kit and tetra kit player parts. That’s the flow you’d normally use in a real environment.

@@cemaxecuter7783 Outstanding, thanks very much for the info! Also, while I've got you in the thread, is there a way we can donate to you?

Well, I’ve not actually collected anything from it yet cause it’s fairly new - but to the best of my knowledge anything donated here should become available to me haha www.patreon.com/cemaxecuter I have it setup, have to go check how to pull something out. Anything that goes in, goes towards the project in some way shape or form. And thank you for asking and for using DragonOS.

That’s great to hear! I have no tetra near me and only had a short IQ file someone sent me so that I could make sure the tetra kit and player worked. Is this the project you mean brmlab.cz/project/tetrapol/start? Seems interesting, I could try and see if it works.

hello, yes that is the project that I tell you. If you ever need Tetra or Tetrapol IQ, tell me and I'll be happy to send it to you. Thanks again

I think maybe a problem is the project is some 7 years or so old and seems to count on gnuradio - so I suspect it’s for a very old version.

Unfortunately I’ve never been able to test it well as there’s no tetra here. I’ve had to count on someone to send me a IQ of tetra to test it. My understanding is that SDR++ is working on a tetra plugin and there’s also another already existing 3rd party plugin for it. If I could get another IQ or Wav recording perhaps I could test it.

I’d have to watch again and brush up, if this is the video I thignk it it is someone provided me an IQ recording that I was playing back for testing this,

This has me thinking - you wouldn’t perhaps be able to provide an unencrypted capture of tetra at maybe 2Msps recording in Gqrx? I’d like to test this again and do a new video.

@@cemaxecuter7783 hi expert, can you answer my question for help me?

Never heard of a VMs 3000. The flow graph is setup to receive live input from a software defined radio. Is the VMS a software defined radio?

@@cemaxecuter7783 i am sorry for the typo Sir, It is VS3000 a tetra based mobile radio. No sir it is not an SDR. I was thinking of using an osmocom source directly at the receiver chain and transmit from the actual tetra Radio itself and in that way i can skip the complete transmitter part since i am actually transmitting a TETRA based Signal. Please correct me if i am wrong. Moreover sir why is there no audio from the TETRA kit player? Regards

@@cemaxecuter7783 sir im in dire need of help please help me sir

I’m not really following, the flow graph and project is designed to receive and decode Tertra with an SDR. The tetra player works with that by keeping an eye out for decoded files at which point it plays them.

@@cemaxecuter7783 sir my question is,, that here for your demonstration you have used a tetra IQ file however i want to decode an actual signal transmitted using TETRA based radio.

Hi, there’s no conflict. Both work fine. Now I’ve not run them both at the same time, but they do work. How are you starting it? DragonOS has both python3 and 2 installed so you have to take care of how you start thy script.

sudo python3 simple_IMSI-catcher.py -sniff

@@cemaxecuter7783 i did exactly that. but when you open another Terminal to run grgsm_scanner and chooses a frequency, here will see the error message

You run grgsm_livemon on the freq you’ve determined from the scanner, then you run the script once you see the output in grgsm_livemon.

@@cemaxecuter7783 i just did that in the order you told me, and got error messages (Traceback (most recent call last): File "simple_IMSI-catcher.py", line 617, in udpserver(port=options.port, prn=find_imsi) File "simple_IMSI-catcher.py", line 556, in udpserver sock.bind(server_address) OSError: [Errno 98] Address already in use )

Is this walkie talkie a tetra handset? Can you record an IQ file of you using it and saying something? I need a file I can play back for testing purposes.

@@cemaxecuter7783 drive.google.com/file/d/11kWXS9pUetRL_xOenVFeb9-DP6qPfHPJ/view?usp=drive_link

help me pls

i think i dont know how to record an IQ file. Can you show me how?

I don’t think I have access

Not working in DragonOS FocalX? You have to open the gnuradio 3.10 flow graph.

You may need to delete the missing udp block and enable the udp sink that’s disabled.

@@cemaxecuter7783 I tried lesson1 from great Scott gadget and of course it's outdated and not working but it's most difficult "hello world" in the world 😅 It's give me confidence on tool how it's setup. I'm using portapack hackrf and Manjaro distro. Hope will resume to lesson2 😅

You definitely need a good SDR such USRP devices, some additionnals equipments and some good technical skills and comprehension of GSM, UMTS, LTE technologies, so basically the answer is : no you can't using a single 40$ sdr and you should know that trying to intercept confidential data is completely illegal.

Without going into great detail, cause honesty I don’t know all the required bits and pieces off the top of my head, your best bet within a lab environment is having no encryption and trying the “sms” feature of gsmevil2.

Now I tried with the GRC file on gnuradio-3.10 and now it shows more blocks, but it's not starting

@twitch_theoxidado9043 yes it has to be the grc 3.10 flow graph and please remind me which one is red. There’s one block that needs changed..

@twitch_theoxidado9043 open the 3.10 packed flowgraph grc file and it starts fine. If you open the other 3.10 you’ll have to delete the udp block and search for the updated one using the magnifying glass. Or preferably before deleting the old one, look at its settings and match up the new one and reconnect.

​@@cemaxecuter7783I'm gonna try that tomorrow, thanks for your help tho :)

​@@cemaxecuter7783and I have to put the same info in the UDP block? I don't understand the point

Unfortunately I do not have the old file I was testing with.

It’s most likely or or two things, first check your firmware version is 2021 or greater. Second, which source block is in the flow graph? I’ll check in a bit, you will most likely have to open the source block and place hackrf=0 in the device argument section.

@@cemaxecuter7783 hackrf - Firmware Version: 2021.03.1 (API:1.04) The error appears when running gnuradio > Block paths: /usr/share/gnuradio/grc/blocks /usr/local/share/gnuradio/grc/blocks Loading: "/home/mod/.local/share/Trash/files/phy/gnuradio-3.8/pi4dqpsk_rx.grc" >>> Done Generating: '/home/mod/.local/share/Trash/files/phy/gnuradio-3.8/pi4dqpsk_rx.py' Executing: /usr/bin/python3 -u /home/mod/.local/share/Trash/files/phy/gnuradio-3.8/pi4dqpsk_rx.py gr-osmosdr 0.2.0.0 (0.2.0) gnuradio 3.8.1.0 built-in source types: file osmosdr fcd rtl rtl_tcp uhd miri hackrf bladerf rfspace airspy airspyhf soapy redpitaya freesrp [INFO] [UHD] linux; GNU C++ version 9.2.1 20200304; Boost_107100; UHD_3.15.0.0-2build5 [INFO] [UHDSoapyDevice] Opening HackRF One #0 57b068dc22864663... -- Using subdev spec '0:0'. [INFO] [MULTI_USRP] 1) catch time transition at pps edge Traceback (most recent call last): File "/home/mod/.local/share/Trash/files/phy/gnuradio-3.8/pi4dqpsk_rx.py", line 366, in main() File "/home/mod/.local/share/Trash/files/phy/gnuradio-3.8/pi4dqpsk_rx.py", line 344, in main tb = top_block_cls() File "/home/mod/.local/share/Trash/files/phy/gnuradio-3.8/pi4dqpsk_rx.py", line 127, in __init__ self.rtlsdr_source.set_time_unknown_pps(osmosdr.time_spec_t()) File "/usr/lib/python3/dist-packages/osmosdr/osmosdr_swig.py", line 2062, in set_time_unknown_pps return _osmosdr_swig.source_sptr_set_time_unknown_pps(self, time_spec) RuntimeError: RuntimeError: Board 0 may not be getting a PPS signal! No PPS detected within the time interval. See the application notes for your device. >>> Done (return code 1)

I forgot to mention you may need to open the source block and change the timing source