Help Understanding P25

[SCPD]

Is there a reference on the internet to help me understand what I'm seeing for CCDump? I'm not looking for a program to help me. I have attached a txt file of a CCDump from a P25 system. I plan on making a program that not only makes some sort of summary of what's going on, but will link audio to certain IDs and other things. Is EVERY radio (from both sides of the conversation) broadcasted or just the person that starts the new frequency? What line appears when radios are associated? etc.... Thank you all for your help!

 

[DaveNF2G]

Why reinvent the wheel? There are already programs available for free that do all that you describe and much more.

 

[SCPD]

Because its for personal use at the moment. I want to make a program that allows me to queue transmissions so I can review them.

 

[SCPD]

Is there a reference on the internet to help me understand what I'm seeing for CCDump?

Purchase the spec from TIA. Some public or university libraries may have a copy.

 

[MattSR]

Find a copy of TIA-102.AABC-A - Project 25 Trunking Control Channel Messages.

As Rick mentioned, Its the blueprint for P25 trunking.

 

[SCPD]

I'm having trouble locating this, could you point me in the right direction?

 

[MattSR]

IHS - Document Details

 

[SCPD]

Wow... $272.00, I guess I'm out of luck. I checked at my university and they don't have it either :-/

 

[MattSR]

Thanks for that response, I just won a $20 bet with myself

 

[MattSR]

Because its for personal use at the moment. I want to make a program that allows me to queue transmissions so I can review them.

ID Tracker 2 does all of this already. It can record events and talkgroups from a P25 scanner - this is probably your best bet.

Cheers,
Matt

 

[SCPD]

I will give this a try. From the time I started with my first scanner (Pro-106 about 2-3 years ago), I've been getting more and more interested in radio communications and was hoping to create a program and learn from it. Thanks for your help!

 

[WayneH]

You still aren't out of luck. You have software that already identifies it for you so you can use it for a reference as to what messages mean what. There may be some extra information that's not defined in software but that's the fun part of deciphering the code.

11 years ago I started on 3600 Moto trunking and I had little to no info on the CC messages. Buying manuals and learning how systems operate will teach you a lot.

 

[SCPD]

True. Also had NO idea about this kind of software. ID Tracker III basically came up with most of my ideas. The only problem I have with it is that when people release the PTT key when talking, it stops recording or switches to a new segment (because its sometimes a new frequency) - Probably nothing that can be fixed

 

[loumaag]

True. Also had NO idea about this kind of software. ID Tracker III basically came up with most of my ideas. The only problem I have with it is that when people release the PTT key when talking, it stops recording or switches to a new segment (because its sometimes a new frequency) - Probably nothing that can be fixed

Bring this up with David (the author). He is a DB Admin and active here on the site.

 

[SCPD]

True. Also had NO idea about this kind of software. ID Tracker III basically came up with most of my ideas.

Clever man that David.

The only problem I have with it is that when people release the PTT key when talking, it stops recording or switches to a new segment (because its sometimes a new frequency)

That doesn't sound like a problem. When the mobile unit stops talking - the conversation is over. Why continue to record dead air?

 

[SCPD]

Actually, most of the time they stop talking for 5 seconds (enough for it to switch frequencies) but they are still in the same conversations (for example, they are thinking about something or just a slow officer)

 

[SCPD]

Actually, most of the time they stop talking for 5 seconds (enough for it to switch frequencies) but they are still in the same conversations (for example, they are thinking about something or just a slow officer)

When the conversation resumes, the program will resume recording, right? I'm not understanding the problem.

 

[SCPD]

It doesn't for me. This could be because of certain settings on my scanner (like priority) or maybe program settings.

 

[SCPD]

Sorry to bring up an old thread but I've seem to hit a dead end. When I use Pro96Com, it works when I Analyze the system. When I do this myself in C# and reading the serial port, it doesn't have any messages. It only shows:

P25:T0000:0090025A0259025A02596A1B
P25:T0000:8590000000000000000035F7
P25:T0000:020001AF000701910005278C
P25:T0000:09900A00000000000000A7C1
P25:T0000:BB0000BEE0014401B970E51E
P25:T0000:3C00003144010E0575705287
P25:T0000:3900010101390401D704581F
P25:T0000:BD001325E032091B94C412AC

When I move to scan or tune, it shows the messages. What is Pro96COM doing to get these messages so that it doesn't have to be in scan where it stops when a transmission goes across?