Scanning Provoice digital radio systems

[mayfiejb]

If I were to purchase a radio such as a pro-96 would I be able to listen to Ma/Com ProVoice digital transmissions? As I uderstand it, ProVoice Digital and apco-25 are incompatibe. Does this mean that the radio will not track the conversation or does that mean that I will not hear any recognizable transmission? I have read that the systems use the use the same vocoder.

 

[Colin9690]

Simply put, you CAN'T listen to Provoice (no scanner can), but you CAN listen to APCO-25 on a PRO-96.

And regarding to Provoice, the scanner simply won't track the conversation, so no one can listen to provoice unless they buy a professional Provoice radio.

Hope This Helps,

 

[SCPD]

pro voice

Even if it were as simple as strolling down to WalMart and getting a PV radio, and where would one buy one anyway, the radio would have to be setup to operate on the particular freqs and groups that the system uses. And then wouldn't it have to be changed everytime you wanted to listen to another dept?
It would seem in the last 3-5 years some progress would have been made in beingable to monitor ProVoice systems. Has there been any progress, any at all?? I hate the fact that all these communities try to hide all comm from the taxpayers.

 

[rmiles]

It would seem in the last 3-5 years some progress would have been made in being able to monitor ProVoice systems. Has there been any progress, any at all??

The problem is M/A-Com will not release the proprietary ProVoice codec. In order for a scanner manufacturer to legally produce a ProVoice capable scanner, M/A-Com would have to release the codec and license it to said producer.

 

[N_Jay]

The problem is M/A-Com will not release the proprietary ProVoice codec. In order for a scanner manufacturer to legally produce a ProVoice capable scanner, M/A-Com would have to release the codec and license it to said producer.

Except as it is a DVSI vocoder.

I doubt N/A-COM controls it but I am sure DVSI would want a cut.

Personally, I think the issue is that the market for a ProVoice scanner is just not big enough.

 

[mitaux8030]

There's two parts or aspects to consider.
IMBE is the technology for turning voice into a compressed digital format.
ProVoice is the technology that encodes this compressed digital format onto a radio carrier.

IMBE can be bought, at a price, from DVSI. This is how a P25 tracking scanner has some into being - Uniden, GRE et al have licenced the IMBE vocoder in their products, and you pay the premium in the purchace price.
ProVoice however, remains something that MA-Com wants to keep to themselves.

 

[N_Jay]

There's two parts or aspects to consider.
IMBE is the technology for turning voice into a compressed digital format.
ProVoice is the technology that encodes this compressed digital format onto a radio carrier.

IMBE can be bought, at a price, from DVSI. This is how a P25 tracking scanner has some into being - Uniden, GRE et al have licenced the IMBE vocoder in their products, and you pay the premium in the purchace price.
ProVoice however, remains something that MA-Com wants to keep to themselves.

I would think it would be almost impossible to patent or copyright channel coding.

 

[rmiles]

Personally, I think the issue is that the market for a ProVoice scanner is just not big enough.

I think your WAY underestimating this. There is a HUGE demand for a PV capable scanner.

PV is a proprietary digital voice codec and will not be released into the public domain without MAJOR pressure exerted on M/A-Com to do so. Say something like the loss of a major contract unless they release the codec so VOL FF/EMT, AUX PD, media, etc. can monitor, or more likely, so other radio manufacturers can produce those radios. I remember reading somewhere that was a stipulation in the NY OpenScam contract. NY wanted M/A-Com to release the OpenSky protocol so other companies could provide subscriber equipment. NY did not want to be locked into a sole source equipment provider, and wanted their many VOL FF/EMT's & AUX PD to have the ability to monitor appropriate TG's without the need for a radio. Due to the nature of OpenSky, I don't see how that would be possible but it was a contract stipulation at one point in time.

They use the proprietary nature of the codec as a major selling point too!

 

[N_Jay]

I think your WAY underestimating this. There is a HUGE demand for a PV capable scanner.

Marketing data?

PV is a proprietary digital voice codec and will not be released into the public domain without MAJOR pressure exerted on M/A-Com to do so.

No, PV is a combination of a DVSI vocoder (IMBE) which is available in several forms, and a proprietary channel coding that may or may not be well protected.

I remember reading somewhere that was a stipulation in the NY OpenScam contract. NY wanted M/A-Com to release the OpenSky protocol so other companies could provide subscriber equipment. NY did not want to be locked into a sole source equipment provider, and wanted their many VOL FF/EMT's & AUX PD to have the ability to monitor appropriate TG's without the need for a radio. Due to the nature of OpenSky, I don't see how that would be possible but it was a contract stipulation at one point in time.

Yep, but that is OpenSky and not ProVoice.

They use the proprietary nature of the codec as a major selling point too!

Again, it is not the "codec" (vocoder).

 

[ElroyJetson]

Your only option is to buy a ProVoice-enabled M/A-Com or Ericsson/GE, etc. mobile or portable radio and have it programmed appropriately. Which isn't impossible, but it requires you to know the right people.


Elroy

 

[Rescue1]

So Elroy,if I knew someone then I could hop on the system,unlikely but you make a good point.But by chance(I don't but in theory) if someone has a provoice radio like an LPE-200,with the software and hardware can they then listen in?? Is there a form of a system key like MOT uses to futher secure the system?I have always been curious about MA-Com's setup,thanks..

 

[ABBAFATHER]

So Elroy,if I knew someone then I could hop on the system,unlikely but you make a good point.But by chance(I don't but in theory) if someone has a provoice radio like an LPE-200,with the software and hardware can they then listen in?? Is there a form of a system key like MOT uses to futher secure the system?I have always been curious about MA-Com's setup,thanks..

You can listen to Provice conversation when you have a Uniden 396t and turn down the squelch all the way, and your near a site. You will hear conversation periodically.

 

[N_Jay]

You can listen to Provice conversation when you have a Uniden 396t and turn down the squelch all the way, and your near a site. You will hear conversation periodically.

Ah, Nope!:roll:

 

[ABBAFATHER]

Ah, Nope!:roll:

Try it?

 

[N_Jay]

Try it?

Don't have to.

Because I don't believe in magic.

You may be hearing analog transmission on the same frequencies, or analog traffic on the trunked system, but you are NOT hearing Pro-voice transmissions.

 

[ABBAFATHER]

Don't have to.

Because I don't believe in magic.

You may be hearing analog transmission on the same frequencies, or analog traffic on the trunked system, but you are NOT hearing Pro-voice transmissions.

According to the id tags I am listing to Pro-vice transmissions. I even now the Police department car numbers and they correspond.

 

[N_Jay]

According to the id tags I am listing to Pro-vice transmissions. I even now the Police department car numbers and they correspond.

OK, well in that case;
1) you have a magic scanner
or
2) you are mistaken
or
3) you are lying
or
4) you are a troll
or
5) the units you hear are transmitting analog

 

[ABBAFATHER]

OK, well in that case;
1) you have a magic scanner
or
2) you are mistaken
or
3) you are lying
or
4) you are a troll
or
5) the units you hear are transmitting analog

You should not jeer people, and call people names you do not know. Especially when you have not tried some thing they have tried.
I am none of the above either.

Ma/Com Pro-Voice digital transmissions is "EDACS is recognized as a reliable, fault tolerant, trunked two-way radio communications system". But if it cannot transmit in Pro-Voice (Digital) it has a default to go automatically to analog. And with the squelch down all the way, and your near a site with a Digital Scanner what do you think. Think about it if the Pro-voice failed whats the back up if the platform is EDACS.

 

[davidbond21]

Personally, I think the issue is that the market for a ProVoice scanner is just not big enough.

I think N_Jay is right about this. There may be a huge demand in areas that use ProVoice, but that demand diminishes significantly when placed at the national level, where the use of ProVoice is not widely distributed(though I'm sure this is growing).

What I'd like to know is how many people have had success trying out the Digital Voice Conversion Method in the wiki(http://wiki.radioreference.com/index.php/Digital_Voice_Conversion_Method). It looks like this is the only alternative to being in good graces with the system administrators on ESK enabled systems.

 

[davidbond21]

And with the squelch down all the way, and your near a site with a Digital Scanner what do you think. Think about it if the Pro-voice failed whats the back up if the platform is EDACS analog.

Well, with the squelch all the way down, who knows what your are picking up (though if close to a site, it may be off that).

Just because you are seeing talkgroups you have labeled as ProVoice, doesn't mean you are hearing ProVoice transmissions. Where I am, the PD is exclusively ProVoice(a lot of analog channels for other agencies though on the same system), but usually, one of the dispatches will also be simultaneously broadcasting a analog signal for whatever reason, but I can only hear the dispatch side of the conversation because only the dispatch console can transmit both, hand held units aren't capable of that.

I've never used a Uniden, but on the Pro-96 and PSR-500, when you are hearing analog voice, it displays "VC" next to the frequency for voice channel. If it is digital, it displays "DG" to indicate it is P25 voice you are hearing. I would think your scanner would have something like that, and if it does, thats something to pay attention to when you go back out to the site and turn your squelch down to listen to the ProVoice system.

Also, if the trunking system went down, probably all public safety radios are programmed to operate on some simplex frequencies. If a EDACS ProVoice system went down, why would it revert to analog, when trunking operations have ceased?

I'm sorry if I come off as condescending, I'm not trying to be. I just think you're a little confused. Read up on ProVoice and P25 voice, as well as some of the other proprietary protocols, and I think you'll gain a better understanding of what you are hearing.