Programing a Trunked radio for monitoring only

[swilkos]

First, if this is off topic based on the forum rules, would a moderator please remove it. I've read through the rules and I don't believe that is the case. That said:

Is it possible to aquire a radio and have it programmed for reception of a public safety trunked system? I realize that you can do this with scanners (and currently do), but have always found that you get better reception when you are using a commercial radio. In our area there are a variety of trunked systems, including a large statewide system, and I'm trying to determine the feasability of installing commercial radios to monitor the trunked systems.

So the main question, is it possible to do this, and if so, would the local dealers be the best place to look?

Thank you,
Scott

 

[kb0uxv]

No, it is not possible. First, the radio would be rather expensive to support the trunking features. It is much cheaper to get a scanner. Second, you would not be able to program the trunking system unless you had the system key, and only the systen admin is able to release it. Finally, each radio on the system needs a unique ID code and only the system admin can create the ID and load it into the system.

 

[medictod]

Anything is possible.
And what your asking is done all the time.
Don't let anyone discourage you, as you are right about one thing, radios born to do trunking make great trunking radios..

 

[Skypilot007]

Yes it is possible. But you will have to research the topic yourself and learn alot. Go over to batboard and do so some searching. It's all there.

Just to touch on some items kb0uxv mentioned, trunked motorolas can be had for less than $200.00 or less on ebay these days. System keys can be created with a hex editor. Once its working correctly it doesn't matter what radio ID is in the radio because the system administrator will never know its there when programmed properly, it will function just like a scanner...almost

There are down sides to using professionsl radios as trunked scanners. Your scan lists will be limited to 10-16 channels depending on the radio and it is quite a job to figure all this stuff out and get it programmed right. Have fun

 

[kb0uxv]

Sure anything is possible. You could go rob a bank, that would be possible. But not legal, just like its not legal to put your unauthorized radio on a trunking system. Here it is a felony. If you are smart enough to hack a radio onto a trunking system and grab a ID that is working, you force the legal radio to slave to your radio. Now the police officer screaming for help on his law main is actually talking on whatever talkgroup you have your radio set to. You can get somone hurt, and you can bet when the admin sees a duplicate ID on the system they will start to track you down. If you have a working ID on a trunking system, at least a P25 system (I have no knowledge of other types of trunking systems), it is a legit user ID. IDs not created will not work. Don't be stupid, if you currently doing this on a P25 system you need to knock it off before you get someone hurt.

 

[swilkos]

Thanks for the replies. I didn't realize it would be such a hot topic, and reading between the lines, I can see why.

Thanks again!

 

[jf4164]

I have a couple of Motorola MTS2000's that I programmed for local trunk systems. All you have to do is set the parameter for "do not transmit" when programming. Radios work fine as high priced scanners. I have the software legally and just wanted to use the radios for monitoring. They hear and track every talk group my "legal" government issued radio does--they just do not transmit and the system does not even know they r there...

 

[kb0uxv]

Yes, the radio works and you receive audio. You are also right that your Motorola sounds far better than any scanner on the market. But if you have a radio ID in your trunking system, your radio is still affiliating with the system. I know its fun to program radios yourself and figure out how things work, but this is very dangerous when you don’t know about how the SYSTEM as a whole works.

For example:
My radio is #123 and I am affiliated with the system on LAW MAIN. The system knows this (from the control channel) and sends audio from this talkgroup to my radio.

You buy your own radio, hack the system key, and just pick some random ID number, which happens to be mine, #123. You affiliate with the system (even though you have voice TX disabled) and set your radio to FIRE TAC1. The system now sees radio #123 is set to FIRE TAC1 where it was previously on LAW MAIN (when my LEGAL radio was on). Now I start to hear your FIRE TAC1 traffic on my radio. Whats worse, I key up to call for help and now that audio is going out on FIRE TAC1. There is no dispatcher listening to this talkgroup. And you, with the hacked radio, don’t even realize this is going on.

See how dangerous this is?

 

[rescue161]

It's EASY. Set the radio to "Do Not Affiliate" and the radio will never affiliate.

With the Spectra line of radios you can add extra security that the radio will never affiliate.

1) Set the radio to TX Inhibit
2) Do NOT connect the Orange wire to 12VDC (You also have to tell the radio to not TX when 12V is not applied to the orange wire)
3) Set the radio to not affiliate to the system.

As said earlier, it won't matter what the radios ID is, the system will never know that it's there and it will not interfere with the system.

 

[chrismol1]

oh no here we go again!

"Programing a Trunked radio for monitoring only"

Short answer to newbies? NO
theres a bit of technical knowledge required before attempting stuff like this even then it sometimes gets complicated
As kb0uxv said below - Not all radios work the same when your trying to do this
Best security measure is to remove the PA/transmitting components completely

 

[kb0uxv]

My experience is with ASTRO 25 using 2500s, 5000s, and APX. I see no way to disable affiliation using CPS. What you describe appears to only apply to legacy systems and radios.

 

[rescue161]

My experience is with ASTRO 25 using 2500s, 5000s, and APX. I see no way to disable affiliation using CPS. What you describe appears to only apply to legacy systems and radios.

The OP mentioned nothing about P25 or 9600 Baud systems. He mearly wanted to know if a radio could be programmed as receive-only on a trunked system and people jumped to conclusions. Point being, a radio CAN be programmed on a system to not affiliate and NOT cause harmful problems if done correctly.

P25 9600 Baud systems are a bit different.

 

[n5ims]

The OP mentioned nothing about P25 or 9600 Baud systems. He mearly wanted to know if a radio could be programmed as receive-only on a trunked system and people jumped to conclusions. Point being, a radio CAN be programmed on a system to not affiliate and NOT cause harmful problems if done correctly.

P25 9600 Baud systems are a bit different.

The issue is that although it can be done on older systems using older radios, it normally isn't a trivial task. If not done correctly, it will at best cause you to transmit on an unauthorized frequency and at worst may cause issues with valid users on the system.

 

[chrismol1]

I wonder what kind of trunked systems were talking about? If we knew we can be more specific

 

[swilkos]

I really appreciate all of the replies. For those that have been a bit harsh in your responses: Not everyone is out to screw the system, or do things illegally. An honest question was all I was asking, because I know for a fact commercial radios receive better then scanners. If the answer is "It would be illegal to do x, y or z" then the answer is simple, because I won't do it.

To those that have responded with information, the system in quesiton is the Durham NC County trunking system. It's a motorola system, and I do not believe they have moved up to P25 yet. Most of the other agencies in the area are running on the VIPER system which is a P25, and I hadn't even thought of doing anything but using the digital trunking scanners I have. But as busy as Durham Fire and Police are, I'm just exploring options available. Again, if it's not possible to legally use a commercial radio, then it's not an option. But, if it is possible on certain models with non-affiliation, then those are options I'd like to explore.

Thanks!

 

[chrismol1]

Unfortunately this topic is brought up a lot and gets heated. The problem is that many have no intent to screw with the system but infact thats just what is going on. This is when everyone jumps to conclusions with the "Affiliation Rant".
To clear things up
According to the database here

Durham's 800Mhz System is a 4 site Smartzone 4.1 mixed mode (analog & digital) system.
The four sites operate in simulcast as one Smartzone site.

 

[Skypilot007]

Sure anything is possible. You could go rob a bank, that would be possible. But not legal, just like its not legal to put your unauthorized radio on a trunking system. Here it is a felony. If you are smart enough to hack a radio onto a trunking system and grab a ID that is working, you force the legal radio to slave to your radio. Now the police officer screaming for help on his law main is actually talking on whatever talkgroup you have your radio set to. You can get somone hurt, and you can bet when the admin sees a duplicate ID on the system they will start to track you down. If you have a working ID on a trunking system, at least a P25 system (I have no knowledge of other types of trunking systems), it is a legit user ID. IDs not created will not work. Don't be stupid, if you currently doing this on a P25 system you need to knock it off before you get someone hurt.

I don't mean to insult your intelligence but you obviously do not understand the way one of these radios can be simply programmed as a receive only radio on most motorola systems, even 9600 P25 systems. The radio will never affiliate with the system if programmed properly, PERIOD end of story. Therefore the rest of your post is pointless. No cop anywhere is going to have problems with just another scanner listening in on them. Thats all it is.

 

[rescue161]

That system in question is not a 9600 Baud system, so it can very easily be monitored without affiliation as long the radio is programmed as Type II and NOT as SmartZone.

If someone screws around and tries to program their radio so they can hear the connect tone when they press the PTT, that's when the problems will arise.

 

[kb0uxv]

Skypilot, You won't get an arguement out of me, I know its a waste of time on the internet since no one is ever wrong. All I know is that these affiliation issues are occuring as we speak, it is time consuming to track down the offenders, and critical traffic has been missed because of it. Please explain how an enthusiast can use CPS on a XTL/XTS on a 9600 P25 system without affiliation. Then the techies here on Radio Reference can do it your way without causing problems on systems.

 

[Seadoo]

kb0uxv, I see your fustration. You can only tell people what not to do, if they are going to do it, they are going to do it. You are correct as far as P25 systems go, there is no way to disable auto affilliation on a p25 system, but legacy type II systems can have a radio only affilliate on PTT. Now with the new rebanded systems" depending on how the trunking system is set up after rebanding, it can allow or not allow a radio to be programmed with "affilliate on ptt" function, even though the radio set it up that way in the cps. On our type II system, we have configured the auto affilliate on powerup function, and if a unauthrorized radio is programmed with affilliate only on ptt, the radio will not lock onto the control channel and give you either OUT OF RANGE or NO COMMS on the display. if KS4VT saw this thread, he would be screaming like you and me are as well. It is very dangerous and not a good idea to program a unauthorized radio to a system that you are not supposed to be on. Swilkos, I see your just inquiring, so im just giving you some answers.