Sync:-NXDN48 CB VOICE

[BTJustice]

I am trying to listen to a local police department using SDR+ and DSD+. I keep seeing this and have no idea what it means...

"Sync:-NXDN48 CB VOICE"

Does the - mean encrypted and therefore cannot be decrypted and listened to? Regardless, all I hear is a garbled mess.

 

[racingfan360]

>Does the - mean encrypted
No. the decode shows you've synced to the signal, the "-" means -ve polarity (it could be +ve) NXDN48 indicates very narrow NXDN, CB is Conventional Base (ie a non-trunked repeater) and Voice obliviously). As you're not seeing e:..... after this then it's error free decoding.

However, as you just hear garbled mess then that's almost certainly encrypted :-( DSD+ doesn't indicate encryption on NXDN decodes (it does on P25 and DMR). If you want confirmation, upload a raw sample to something like zippyshare and I'll check it.

 

[wbswetnam]

However, as you just hear garbled mess then that's almost certainly encrypted :-( DSD+ doesn't indicate encryption on NXDN decodes (it does on P25 and DMR).

How does DSD+ show encryption? Fortunately up until now I haven't encountered any enc signals by the local PDs and FDs using DMR or NXDN.

 

[racingfan360]

>How does DSD+ show encryption?
Have a look at this screenshot:
http://forums.radioreference.com/voice-control-channel-decoding-software/295152-dsd-status.html

It shows (Enc)rypted group calls on a MotoTRBO system

 

[BTJustice]

Here is a decent sample...

Zippyshare.com - Sample -NXDN48.wav

I am trying to listen to a local police department using SDR+....

I meant SDR# / SDRSharp. My bad.

 

[moj]

It also sounds like the icom idas i'm trying to monitor , I will record a raw sample jhampton and put a sample of what I'm hearing on a zippyshare file aswell and hopefully you will be able to help understand the details etc but to be honest I think there using either a ut-109R or UT-110R board on the transmissions that I,m hearing but not sure so still worth a try .

 

[moj]

Zippyshare.com - DSDPlus-Raw-Input_2015-@013416 new.wav

Hopefully that helps

 

[slicerwizard]

Here is a decent sample...

Zippyshare.com - Sample -NXDN48.wav

That is NEXEDGE with 15 bit voice scrambling.

Zippyshare.com - DSDPlus-Raw-Input_2015-@013416 new.wav

Oh bollocks, that dodgy sample is IDAS with 15 bit voice scrambling. A load of tosh, innit?

 

[BTJustice]

That is NEXEDGE with 15 bit voice scrambling.

Absolutely no way to listen to it then?

EDIT...

DAMN!

Q06: Is there a digital encryption feature in NXDN™?

A06: A 15-bit digital voice scrambler is a standard feature in the NXDN™ protocol. It does provide superior communications security compared to most standard analog voice scramblers. The NXDN™ digital voice scrambler has over 32,000 codes.

 

[moj]

Thanks for that slicerwizard ,so does that mean that the idas sample i sent you is using a ut-109r non rolling or a ut-110r rolling scrambling board to do this encryption , and also why did it appear dodgy ?

 

[slicerwizard]

Thanks for that slicerwizard ,so does that mean that the idas sample i sent you is using a ut-109r non rolling or a ut-110r rolling scrambling board to do this encryption

Those look like add-on voice inversion boards for analog radios. IDAS uses digital voice and the 15 bit encryption would be implemented in the radios' standard firmware, no add-ons required.

and also why did it appear dodgy ?

Call it a hunch...

 

[moj]

Well I tried programming it into my idas handheld but no matter what ive tried I hear no audio what so ever so its well setup and seeing as I can hear the scrambled audio through my funcube I was hoping to descramble it with my radio but so far my plan has failed

And I think its my local pubwatch at night but I wont know till I descramble the transmission somehow so any pointers are welcome

and I,m now guessing that the icom ut- boards are useless then on digital and are only made for scrambling analogue transmissions only ?

thanks again for analysing the sample

 

[balibago]

Good luck

I figured out one time it would take 3 months to test 32000 possibilities. Would it be possible for one to record a scrambled signal then use one's own radio to test one possibility at a time rather than have to wait for them to transmit again? For informational purposes only!