Sds200 audio type

[dave3825]

Monitoring an analog smartzone system with some P25. One tg keeps coming up with digital buzz and not playing digital audio. Audio type for the tg is set to all, do to the analog/P25 mix on the system. So shouldn't analog and digital play if set to all? Am I missing a setting somewhere? Tg was also in the clear on Unitrunker.

 

[tvengr]

In the database, does the talkgroup show analog, mixed, or digital?

 

[GTR8000]

The bottom line is that the Suffolk County SmartZone system is well documented in the RRDB and has been for years. There is no reason for you to have the talkgroups setup as All in the scanner, when they are strapped either for analog or P25 CAI modulation. They should be programmed into the scanner the way they are listed in the RRDB. Analog audio type for the majority of them, with Digital audio type for the P25 CAI talkgroups (identified by the D in the mode column). And of course if the talkgroup is P25 CAI secure, you're not going to hear anything.

 

[Ubbe]

So shouldn't analog and digital play if set to all?

It should. If it can decode the data it should switch to digital mode.

Am I missing a setting somewhere? Tg was also in the clear on Unitrunker.

If it was in the clear on Unitrunker, at the same time, it sounds strange. I'm not familiar with Unitrunker but if it's something like DSDPlus, or if you can install that and use, it will show what type of digital modulation it is and if it actually can decode it while at the exact same time are silent on the SDS200.

/Ubbe

 

[GTR8000]

it will show what type of digital modulation it is and if it actually can decode it while at the exact same time are silent on the SDS200.

There is no question about what type of modulation it is. It's P25 CAI on a Motorola 4.1 SmartZone system. He needs to set the audio type on the scanner to Digital and forget about All, there is no reason to use All in this circumstance.

 

[Ubbe]

In this case it was a good thing to have it on All as he then noticed that the scanner cannot decode the digital data. If he had set it to do only digital he would never had known about the problem. If it actually decodes fine on Unitrunker then it seems to be something that his SDS200 cannot decode. I would recommend to always us All as that will actually let you know what the scanner does and doesn't do and you will sometimes also be aware of any interferencies that could occure on the frequency.

/Ubbe

 

[GTR8000]

In this case it was a good thing to have it on All as he then noticed that the scanner cannot decode the digital data. If he had set it to do only digital he would never had known about the problem. If it actually decodes fine on Unitrunker then it seems to be something that his SDS200 cannot decode. I would recommend to always us All as that will actually let you know what the scanner does and doesn't do and you will sometimes also be aware of any interferencies that could occure on the frequency.

/Ubbe

What are you talking about? This is a Motorola TRUNKED system, not a "frequency". The talkgroup in question is using P25 modulation, period.

 

[Ubbe]

TG's don't just magically float in the air by themselves. They have to be carried by a frequency that are modulated. All TG's in all system types will always use a radio frequency.

/Ubbe

 

[sonm10]

To clear up some confusion,

Motorola type ii and Smart zone systems for all intensive purposes are the precursor to the P25 we all know today. Control channel is obviously digital, but the talkgroups can either be analog or digital.

Post #3 is most correct

 

[GTR8000]

TG's don't just magically float in the air by themselves. They have to be carried by a frequency that are modulated. All TG's in all system types will always use a radio frequency.

/Ubbe

You missed the point.

 

[dave3825]

Wow

In the database, does the talkgroup show analog, mixed, or digital?

There is no reason for you to have the talkgroups setup as All in the scanner, when they are strapped either for analog or P25 CAI modulation. They should be programmed into the scanner the way they are listed in the RRDB.

He needs to set the audio type on the scanner to Digital and forget about All, there is no reason to use All in this circumstance.

In this circumstance, the tg is marked as analog in the database but, looking at the tg history in Unitrunker, it seems the tg has been using mixed analog and P25 (starting back in July) so wont setting to digital exclude any analog and wouldn't ALL be the correct route?

In this case it was a good thing to have it on All as he then noticed that the scanner cannot decode the digital data.

Very true. Not a system I monitor that often with the 200 but if something is set wrong or not working correctly, I would rather know now than later.

To clear up some confusion,

Post #3 is most correct

Post 3 would be most correct only if tg's marked A were only analog and tg's marked D were only digital. This tg seems to now be mixed I will submit it to be changed to M later on.

So the original question was if a tg is set to "all" in the audio type, should it play analog and digital based on what's actually transmitting? Maybe @JoeBearcat could clarify and also advise if he has received any other reports like this?

 

[GTR8000]

In theory, yes, setting the SDS to "All" should allow it to decode either analog or digital modulation. Why isn't it working for you? Who knows.

What talkgroup are you seeing this behavior on, and are you actually seeing frequent mixed-mode usage? Or did the talkgroup switch over from analog to digital? Is this talkgroup patched to the P25 system, or is it exclusive to the SZ system?

A screenshot of the history of calls on this TG from Unitrunker might make things a bit clearer. There were some issues with SmartZone systems in recent Unitrunker 2.1 releases, so make sure that you're up to date, otherwise what you're seeing in the software might not match reality. In fact, there's a good chance that some of the history has already been irreversibly corrupted at some point from the releases that had bugs in them.

 

[JoeBearcat]

It would be useful to see if the issue occurs when set to digital (only).

 

[dave3825]

@JoeBearcat The tg is not very active and the only way to know would be to watch unitrunker at the same time to see what's going on at the time of the call.

When ever I go out, my 200 is with me. I guess I could set it to digital and review UT logs later in the day.

What county and state are you in and do you have a 200?