Determine digital signal type with BC346XT

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suriname

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Hi all...

Before I take the plunge to purchase a digital capable scanner, I would like to know if I can use my current (and only) scanner, the Uniden BC346XT to decode the information from digital-trunking system's control channels.

I'm pretty sure I cannot listen to them with my current scanner, but just want to know if this radio and the decoding software can tell me there is a digital voice system I can listen to.

I hear "control-channels" on my current (non-digital) scanner, but these could also be data-only. I'm trying to find out if there is digital-voice also...

Tnx !!
 

rbrtklamp2

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you do not own a digital scanner and can not decode digital signals with it. so when gewecke said to get a 396xt he is right you will not dedode digital witout a scanner that is made to decode digital like the 396xt. as for software you can always look up how to put a discriminator tap in your 346t and try and decode digital voice with the dsd software package. but that is a small board inside that radio so I hope your soldering skills are good I had a radio die haveing a tap put into it because the person doing it for me held the iron on the soldering pad to long so please becareful when you try that as you may not have a 346 any more after you try. and then you have to learn how to use linux and make and install DSD in it(not easy) plus you have to find the DSD sodtware as megauploads has been pulled from the web and they were the host for DSD 1.4.1 and MBELIB 1.2.3. so I would be a little nicer to the people on the boards here because you may need more help in the future if you do not plan on buying a digital cpable scanner. lastly gewecke has helped more people on this forum with more things than you can ever imagine hes een helped me so before you start going nuts on the board how about remembering you came to the board for help we didnt go looking foe you so show some respect to your fellow radio reference members, no go see if the mod doesnt agree with that
 

Jay911

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The 346 is usable with Unitrunker for any system type that the 346 can decode. That may seem like a roundabout answer, but it isn't. Here's the long answer.

The 346 has "CC Dump" capability, where it can output control channel data. It will do this for any radio system with a continuous control channel that the 346 knows how to decode. That is essentially EDACS and Motorola 3600 (Motorola Type I and Type II) systems. It will NOT decode 9600 (P25) systems.

All 9600/P25 systems are digital.. but that does not mean that the 346 will not decode any digital systems' control channels. Motorola 3600 baud systems and EDACS systems both have the capability to be mixed mode analog and digital (even "all" digital with no analog). So you could use the 346's CC Dump to let Unitrunker show you all the trunk system usage on any EDACS or Motorola 3600 system, even one with digital audio; but systems that the 346 cannot natively monitor, like the 9600 baud P25 system (sometimes called "Motorola P25" erroneously), will not come through the CC Dump.

CC Dump also does not work on other systems that neither the 346 nor any other scanner can decode, such as MPT1327, NEXEDGE, or MotoTRBO. Nor can it help you with systems that don't have a true constant data control channel, like LTR.

Does that help?
 

SCPD

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Edit: renamed topic from "Scanner type for digital decoding?" to the subject you see now.

Suriname - I can't tell if you find some of the other answers (like Jay911) satisfactory so here's more.

Jay covered the CC dump feature of the BC346XT quite well. The main limitation of the BC346XT is the trunked system must be programmed into the radio before the CC feature is useful. This makes discovering new systems cumbersome.

You must manually find and recognize control channels by sound using a limit search. Then program an empty system into the radio and attempt to decode the control channel. If you guess the wrong system type, you get nothing.

A more flexible solution exists but it requires modifying your radio. See the wiki for more details on a discriminator tap. With a tapped radio, programs like Unitrunker will automatically detect the type of trunking without first programming the radio. A tap will also allow use of other programs to decode other signal formats. See DSD and DMR decoder for examples.
 
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suriname

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The main limitation of the BC346XT is the trunked system must be programmed into the radio before the CC feature is useful. You must manually find and recognize control channels by sound using a limit search.
This I was able to do, I can see the waveform in the software, however nothing happens after that. (should I not be seeing something after a while...?)
I have the audio from my 346xt in my PC's line-in.

A more flexible solution exists but it requires modifying your radio.
Willing to do a(ny) mod on my radio. I though I read that the 346xt does not *require* a mod to do what I want to do, but please share a link if you have one.

Thanks for answering my questions, and staying on topic.
 
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SCPD

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What program are you running?

I do see the waveform, but the software does not do anything yet. So any UNITRUNKER folks willing to help me out ?
Nevermind, I found it.

Unitrunker expects discriminator audio, not speech filtered audio. The digital waveform is distorted when run through a speech filter. The exception to this rule is MPT1327. MPT1327 trunking uses alternating 1200 hz / 1800 hz tones which pass through a speech filter unscathed.
 
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mmisk

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