DSD 1.4 and mbelib 1.2.3 released

[pezcat19]

Hello all,

I am successfully decoding P25 P1 and DMR / TRBO signals with the latest DSD. Brilliant stuff!

I have a question relating to DMR - Is it possible to decode DMO Mode (Direct/Simplex) DMR signaling with DSD? I have a DMR radio here in DMO mode and I can not decode any transmissions from it. The signaling sounds (through my analog receiver) like only ONE time slot is being TX'd in DMO mode- i.e - the transmission is "on-off-on-off-on-off" very quickly...

I can decode local DMR / TRBO systems with no issues. (The received signal from these systems is continuous when voice / data traffic is being transmitted - I assume this is because BOTH time slots are being utilized when running through a DMR / TRBO repeater?)

Cheers all, and keep up the great work!

Pez

 

[dsdauthor]

Means they got samples,most likely have identified the signal,and the vocoders format ,for lack of the tech term,has been determined..

someone's probably got a better answer...

DSD fully supports X2-TDMA which is only deployed in Loudoun, VA and Prince Geroges, MD so far. Both systems also use QPSK modulation so it is important to isolate your scanner to a signal from one tower for good decode. On these systems it is also necessary to scan the frequencies in conventional (non-trunked) mode. It is also highly desirable to use a serial control cable and the -R option to skip over the channels used for GPS data.

P25 Phase 2 systems do not exist yet but when they do DSD will be updated to support them. One thing we know for sure about Phase 2 is that it will use a vocoder already supported by mbelib.

 

[ab3ai]

I finally got around to testing 9600 NXDN and it works great. Didn't work on 4800. Great program!! Thanks for your work!!

 

[c5corvette]

It is also highly desirable to use a serial control cable and the -R option to skip over the channels used for GPS data.

I just loaded Ubuntu yesterday. Getting ready to download the dsd and mbelib files. Not sure what to do from there. Where are the configuration instructions and where do I read up about these things like the -R option, etc? Is there anyother thread for this info / type questions?

 

[Dewey]

I just loaded Ubuntu yesterday. Getting ready to download the dsd and mbelib files. Not sure what to do from there. Where are the configuration instructions and where do I read up about these things like the -R option, etc? Is there anyother thread for this info / type questions?

Dewey

 

[Mike_G_D]

Hello all,

I am successfully decoding P25 P1 and DMR / TRBO signals with the latest DSD. Brilliant stuff!

I have a question relating to DMR - Is it possible to decode DMO Mode (Direct/Simplex) DMR signaling with DSD? I have a DMR radio here in DMO mode and I can not decode any transmissions from it. The signaling sounds (through my analog receiver) like only ONE time slot is being TX'd in DMO mode- i.e - the transmission is "on-off-on-off-on-off" very quickly...

I can decode local DMR / TRBO systems with no issues. (The received signal from these systems is continuous when voice / data traffic is being transmitted - I assume this is because BOTH time slots are being utilized when running through a DMR / TRBO repeater?)

Cheers all, and keep up the great work!

Pez

It's my understanding that these TDMA system radios switch to one slot per frequency when in simplex mode because they lack the master timing signal from the control site which is needed to sync up all of the subscriber units correctly and allow them to accurately differentiate between voice channels in different timing slots. When in simplex mode - direct radio to radio - the timings/oscillators of each radio will all be off slightly relative to each other to the extent that using mult-timed slots would be problematic at best. This is why they simply switch to one voice channel per radio frequency when in simplex mode. This is also another reason that the controller will output continuous data because all of the subscriber radios need that master timing signal to lock onto.

I was wondering if the DSD program would handle the TDMA simplex modes. It appears it doesn't yet do so but perhaps if you use your radio to transmit some messages and record the discriminator output from your receiver you could send the author that data and he/she could develop code to deal with that mode - at least for your system.

This is also one of the "advantages" touted by FDMA pundits over the TDMA systems; FDMA 6.25KHz systems like NXDN do not use master timing signals to separate out their voice channels as they literally are one voice channel per frequency but using very narrow band modulation to ideally allow 4 6.25KHz channels within a 25KHz bandwidth (though I expect that receiver IF filtering will limit that in real world situations when in the presence of strong adjacent channel signals). They can operate simplex and still (ideally) retain their full channel capacity

-Mike

 

[dsdauthor]

I was wondering if the DSD program would handle the TDMA simplex modes. It appears it doesn't yet do so but perhaps if you use your radio to transmit some messages and record the discriminator output from your receiver you could send the author that data and he/she could develop code to deal with that mode - at least for your system.

It turns out the DMR standard uses two different sync words, one for "Base Station" (repeater) transmissions and the other for "Mobile Station" (simplex and repeater uplink). All it took was to add the MS sync to DSD to get simplex/repeater input mode to work. That will be in the 1.4.1 release which I hope will be soon. I want to also get NXDN 4800 mode in that update but I don't yet have a good sample to test with. I am also searching for the MS sync for X2-TDMA Does anyone happen to know that sync already?

 

[Mike_G_D]

Excellent work! Well, there you go, pezcat19!

-Mike

 

[f4jmk]

Great program.
I can decode P25 with no problem, not having any luck with NXDN, I have attached a wav file of what I thought to be a 9600 baud signal, maybe it is 4800?

 

[mrscanner2008]

somes links for info just in cases:

Advanced Multi-Band Excitation - Wikipedia, the free encyclopedia

NXDN - Wikipedia, the free encyclopedia

some audio samples:

W2SJW - Radio Sounds

Digital*Modes*Samples

I hope this could help...

Mrscanner2008

 

[dsdauthor]

Great program.
I can decode P25 with no problem, not having any luck with NXDN, I have attached a wav file of what I thought to be a 9600 baud signal, maybe it is 4800?

It does sound like 9600. I will take a look and see why it is not recognized.

I found the Mobile Station (MS) sync for X2-TDMA so repeater inputs/simplex will work with that format as well as DMR/MotoTRBO in the next release.

 

[pezcat19]

dsdauthor & Mike_G_D,

Thanks guys! I will report back with the results once 1.4.1 is released! (I will also look for a good NXDN 4800 signal... I think I can find one locally here - I will upload it if I have any luck!)

Cheers,

Pez

 

[pezcat19]

dsdauthor,

Changing the topic slightly (sorry) I can confirm that the following hardware configurations are decoding P25 and DMR/TRBO successfully on a mixture of Laptops and PC's (including Asus EEEPC 1000HE, Dell Optiplex GX260 and generic "home built" PC's too).

- Uniden (U)BCD396T - Disc Tap w/100k ohm resistor and 10uf capacitor - fed to PC Line-In (Mic-in on EEEPC)

- AOR AR-2001 - Disc Tap w/10k ohm resistor - fed to PC Line-In. (Mic-in on EEEPC)

- AOR AR-3000A - Disc Tap w/10k ohm resistor - fed to PC Line-In. (Mic-in on EEEPC)


I thought you might like to add the above to your list, (however, any clean discriminator tap should work with DSD, and the list could become huge!!!).

For people wanting some guidance on discriminator taps, have a look here: Discriminator Output

Cheers,

Pez

 

[c5corvette]

Dewey

Thanks!!!

 

[dsdauthor]

The Wiki Page has been updated with the DSD 1.4.1 download link.

NXDN48 uses the exact same voice frames as NXDN96, just with no alternating data frames.

NXDN, DMR and X2-TDMA all use different sync words for repeater output vs input/simplex mode but DSD only had one type for each. This was likely the cause of inability to decode some NXDN and DMR signals. All relevant sync words for these formats should now be included.

Note: NXDN48 (6.25 kHz) requires the -fi option as it uses a different symbol rate than most formats and DSD does not auto-detect symbol rates yet.

1.4.1
New features:
Several new sync types for existing formats now recognized:
Decodes voice from NXDN 4800 (6.25kHz) signals
Decodes voice from NXDN 9600 (12.5kHz) repeater output
Decodes voice from DMR/MotoTRBO simplex/repeater input
Decodes voice from X2-TDMA simplex/repeater input

Fixed bugs:
renamed "input:" to "inlvl:" to reduce confusion. This value
indicates the audio input level, NOT the "decode success
rate". Voice decode errors are indicated by the errorbars "=".

 

[funatic]

dsdauthor,
any chance of having the -pe encryption sync bits option or something like that for TRBO too, useful for determining whether the signal is simply bad or really encrypted?
thanks a lot and kind regards from italy!

 

[funatic]

dsdauthor,
any chance of having the -pe encryption sync bits option or something like that for TRBO too, useful for determining whether the signal is simply bad or really encrypted?
thanks a lot and kind regards from italy!

P.S. one more thing: please could you also tell me which is the best way to play back a .wav file running DSD? not a patch cable ear>mic, i guess...

 

[EagleLink]

Can anyone give me an example of how to use two different sound cards for input and output? I have s modified CM108 USB sound fob I built for using with asterisk as a repeater controller, so I decided to hook it up to a Motorola Radius (pretty simple) and see if I could decode P25. The output on the Radius is discriminator, and I can record and playback through the radio ok, of course I have to hold the MIC PTT to play back through the radio, but it works. What I'd like to do is have DSD get the audio from the USB device and play it back over the internal sound cards speakers.

I tried figuring this out, but I'm a bit confused as to how linux sound devices work.

In the /dev/snd directory I have the following:

controlC0 pcmC0D0c pcmC0D1c pcmC0D3c pcmC1D0c seq
controlC1 pcmC0D0p pcmC0D2c pcmC0D4p pcmC1D0p timer

Near as I can tell, C0 is the internal while C1 is the USB. C1 wasn't there until I plugged in the USB fob. What I am most confused about is which of these devices would I use with the -i and -o parameters to get the results I want. How do I know what each of these is?

Thanks for any help you can give,
Jeff

 

[funatic]

Can anyone give me an example of how to use two different sound cards for input and output? I have s modified CM108 USB sound fob I built for using with asterisk as a repeater controller, so I decided to hook it up to a Motorola Radius (pretty simple) and see if I could decode P25. The output on the Radius is discriminator, and I can record and playback through the radio ok, of course I have to hold the MIC PTT to play back through the radio, but it works. What I'd like to do is have DSD get the audio from the USB device and play it back over the internal sound cards speakers.

I tried figuring this out, but I'm a bit confused as to how linux sound devices work.

In the /dev/snd directory I have the following:

controlC0 pcmC0D0c pcmC0D1c pcmC0D3c pcmC1D0c seq
controlC1 pcmC0D0p pcmC0D2c pcmC0D4p pcmC1D0p timer

Near as I can tell, C0 is the internal while C1 is the USB. C1 wasn't there until I plugged in the USB fob. What I am most confused about is which of these devices would I use with the -i and -o parameters to get the results I want. How do I know what each of these is?

Thanks for any help you can give,
Jeff

Hi Jeff,
for this config (input via the USB device) you would simply use: dsd -i /dev/audio1
The default output is already to the internal sound card.
Ciao from Italy,
Alberto

 

[EagleLink]

USB fob

Ok, before I got the reply I decided to install Ubuntu instead of CentOS because I've seen a lot of people say they use Ubuntu to do this. I don't see a /dev/sound at all in Ubuntu. Should I just swith back to CentOS or is Ubuntu really better in any way? If Ubuntu is better, how would I go about determining the input and output devices as described above?

Thanks,
Jeff