Tetra decoding

sq5bpf · Sep 2, 2015

Pepijn1908 said:
Next step would be to try and do the decoding on the BBB as well but I suspect it won't do that due to its limited resources but I'll try anyway.

telive uses very little cpu and memory, so this won't be a problem. if you don't have enough cpu, then you will get hiccups in the received audio, but there is a workaround:

disable live playing in telive

modify tetrad to play the files that it processes. you can also skip the ogg encoding and save the files as wav. (you can also write some other script to play back the files once they are saved on disk).

since the files that you want to play are already on disk, playback will be much smoother. of course this will introduce a lot of delay, but should work better on slow hardware

sq5bpf · Sep 2, 2015

sam_q said:
The console of GNU radio say PLL not locked.

i don't see gnuradio-companion in the screenshot, so it's hard to tell what went wrong, but my guess is that you're not inputting the frequency correctly. gnuradio uses Hz as the frequency unit, so either input the frequency in Hz, or add the multiplier (M for 10^6, k for 10^3, be careful not to confuse M with m, which is 10^-3). so for example if you want 393.500MHz for the baseband, then enter 393.5M, or 393500k or 393500000, but not 393.500MHz. btw this is described in the documentation

also please use telive_1ch_simple_gr37.grc for the first time. it's much easier to use (no need to worry about the baseband/offset, you can click the spectrum to tune etc)

Pepijn1908 · Sep 2, 2015

sq5bpf said:
telive uses very little cpu and memory, so this won't be a problem. if you don't have enough cpu, then you will get hiccups in the received audio, but there is a workaround:

disable live playing in telive

modify tetrad to play the files that it processes. you can also skip the ogg encoding and save the files as wav. (you can also write some other script to play back the files once they are saved on disk).

since the files that you want to play are already on disk, playback will be much smoother. of course this will introduce a lot of delay, but should work better on slow hardware

Thanks. I have looked at the piece of code you suggested a couple of pages earlier to play the generated files. Will check that.

For now I'm troubleshooting the fact that on my i7 laptop with my bladeRF (RTL-SDR is still coming in from China) the reception is great (90+% of the packages are decoded) and on my BBB with the same receiver and on the same frequency I only get:

BURST
#### could not find successive burst training sequence
found SYNC training sequence in bit #XXX

every now and then. Don't really know why that is but I will check the topblock.py I generated after modifying your gnu blocks again. Maybe I changed or deleted the wrong values.

sam_q · Sep 2, 2015

Works now

sq5bpf said:
so for example if you want 393.500MHz for the baseband, then enter 393.5M, or 393500k or 393500000, but not 393.500MHz. btw this is described in the documentation

You are completly right! ... I use dot in the freq like 395.500000 (Sorry and tanks)

also please use telive_1ch_simple_gr37.grc for the first time. it's much easier to use (no need to worry about the baseband/offset, you can click the spectrum to tune etc)

What is the diference between the "simple" and normal programes?

And the last, works fine now but only for be sure, when says "Air encryption : 1" is encrypted TX? I only hear sounds.

Code:

BNCH SYSINFO (DL 394612500 Hz, UL 384612500 Hz), service_details 0x0d67 LA:6534 CCK ID 96
	Advanced link: 1
	Air encryption: 1
	SNDCP data: 1
	unknown 0x8: 0
	Circuit data: 0
	Voice service: 1
	Normal mode: 1
	Migration supported: 0
	Cell never uses minimum mode: 1
	Priority cell: 0
	De-registration mandatory: 1
	Registration mandatory: 1

BURST
TMV-UNITDATA.ind 31/07/4/000 AACH CRC=1 ACCESS-ASSIGN
ACCESS-ASSIGN PDU: ACCESS2: A/8 DL_USAGE: Assigned control 
CRC COMP: 0x1d0f OK

Thanks 73s

jlxsolutions · Sep 3, 2015

this might be a dumb question or not heh. Is there anyway to figure out the "talkgroups"?

sam_q · Sep 4, 2015

sam_q said:
You are completly right! ... I use dot in the freq like 395.500000 (Sorry and tanks)

What is the diference between the "simple" and normal programes?

And the last, works fine now but only for be sure, when says "Air encryption : 1" is encrypted TX? I only hear sounds.

Code:

BNCH SYSINFO (DL 394612500 Hz, UL 384612500 Hz), service_details 0x0d67 LA:6534 CCK ID 96 Advanced link: 1 Air encryption: 1 SNDCP data: 1 unknown 0x8: 0 Circuit data: 0 Voice service: 1 Normal mode: 1 Migration supported: 0 Cell never uses minimum mode: 1 Priority cell: 0 De-registration mandatory: 1 Registration mandatory: 1 BURST TMV-UNITDATA.ind 31/07/4/000 AACH CRC=1 ACCESS-ASSIGN ACCESS-ASSIGN PDU: ACCESS2: A/8 DL_USAGE: Assigned control CRC COMP: 0x1d0f OK

Thanks 73s

I not explained correctly, I want to say that all is encrypted because say encrypted 1(I read on the documentation that this is not necessary signal of encrypted), but don't hear anything except loud. And if press m for mutessi don't hear anything.

Sorry for the delay on my answers, the forum moderate my post [emoji16]

Enviado desde mi Nexus 5 mediante Tapatalk

sq5bpf · Sep 4, 2015

sam_q said:
What is the diference between the "simple" and normal programes?

try it and find out

the simple flowgraph displays the whole spectrum, and can be tuned by clicking, and hides the offset option which confuses some new users

sam_q said:
And the last, works fine now but only for be sure, when says "Air encryption : 1" is encrypted TX? I only hear sounds.

i have written about this so many times, that i would not like to do it again.

please RTFM , and especially pay attention to everything regarding encryption and mutessi

sq5bpf · Sep 4, 2015

jlxsolutions said:
this might be a dumb question or not heh. Is there anyway to figure out the "talkgroups"?

currently you can't distinguish between ISSI and GSSI, but usually the GSSIs stand out. they often have different numbering schemes, and you will see them in traffic with different ISSIs

just look at numbers which appear often

grahampaull · Sep 4, 2015

sq5bpf said:
currently you can't distinguish between ISSI and GSSI, but usually the GSSIs stand out. they often have different numbering schemes, and you will see them in traffic with different ISSIs

just look at numbers which appear often

Yes, my talk groups are usually 4-5 digits and my issi' are 6-7 digits which is handy.

Sent from my iPhone using Tapatalk

jlxsolutions · Sep 4, 2015

sq5bpf said:
currently you can't distinguish between ISSI and GSSI, but usually the GSSIs stand out. they often have different numbering schemes, and you will see them in traffic with different ISSIs

just look at numbers which appear often

Thanks that gives an explanation to the wierdo numbers often in calls
example's
14703185
6032303_14703993_6022010

now to look up group names and to insert them in description file as they pop up

jlxsolutions · Sep 5, 2015

And i figuerd out how to "fix" the random halts i been having and i am 98% sure it has nothing todo with telive/gnuradio because when it halts it continues if i click in terminal and mouse scroll up and down quick

sq5bpf · Sep 5, 2015

jlxsolutions said:
And i figuerd out how to "fix" the random halts i been having and i am 98% sure it has nothing todo with telive/gnuradio because when it halts it continues if i click in terminal and mouse scroll up and down quick

are you running this in a virtual machine, or are you using ubuntu or mint?

jlxsolutions · Sep 6, 2015

its a virtual machine running Kali Linux

sq5bpf · Sep 6, 2015

jlxsolutions said:
its a virtual machine running Kali Linux

this is probably related to power management on the host OS (windows probably?). please disable all power management, sleep etc and see if this still happens. you can also try to disable vmware tools if they are installed on the guest OS

btw try to run this on normal hardware, running the software in a virtual machine is not recommended for performance reasons, and because of other other strange problems that can arise

jlxsolutions · Sep 6, 2015

power control is always off here and currently i don't have a possibility to run it on straight hardware.
and without vm-ware tools the vm would be a mess.
anywhoms most probably a vm-ware player issue. so till i find some hardware to build a second computer i,ll just deal with.
It happens a few times a day so not a big issue.

jlxsolutions · Sep 8, 2015

Well turns out it was NOT a virtual machine problem and still halts even on actual install....

sq5bpf · Sep 8, 2015

jlxsolutions said:
Well turns out it was NOT a virtual machine problem and still halts even on actual install....

if it halts, and then resumes when you move the mouse, then maybe it is some powersaving feature. try to disable (or uninstall) laptop mode, and see if this helps.

on debian 8 laptop-mode prevents any sdr stuff from running (not enough cpu, and also something else is broken, maybe some usb autosuspend is causing problems), didn't really look into it, as i run mostly on AC, but it is really anoying.

grahampaull · Sep 8, 2015

jlxsolutions said:
Well turns out it was NOT a virtual machine problem and still halts even on actual install....

I haven't used TELive in a good few weeks but a friend of mines contacted me yesterday to say his is freezing after about 15 minutes of use. I've yet to look at this for him.

I wonder did an update get pushed somewhere or is it purely coincidental?

Sent from my iPhone using Tapatalk

jlxsolutions · Sep 8, 2015

sq5bpf said:
if it halts, and then resumes when you move the mouse, then maybe it is some powersaving feature. try to disable (or uninstall) laptop mode, and see if this helps.

on debian 8 laptop-mode prevents any sdr stuff from running (not enough cpu, and also something else is broken, maybe some usb autosuspend is causing problems), didn't really look into it, as i run mostly on AC, but it is really anoying.

It actually froze just 3 seconds after it started and by scrolling up and down in terminal continued.
(you have to actually click inside and use scroll button)
Thou been running fine since then so erh i dunno.

sq5bpf · Sep 9, 2015

grahampaull said:
I haven't used TELive in a good few weeks but a friend of mines contacted me yesterday to say his is freezing after about 15 minutes of use. I've yet to look at this for him.

I wonder did an update get pushed somewhere or is it purely coincidental?

you can look at the updates on github. the only recent update was in the documentation

does it look like the bug jlxsolutions has? (if you scroll the window up/down the process starts to work again)
is powersaving (laptop-mode etc) disabled? (also on host OS if running in a VM)
what distribution? (and is it running in a VM?)

Tetra decoding

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Similar threads