Programing a Trunked radio for monitoring only

[kb0uxv]

I have a question.
I have 2 mts2000's that are programmned for receive only on a trunked system. finally got it done and it works fine.
i have 18 sites programmned in with the control channels only.
when i hit the orange button it is supposed to site scan. it says scanning site but that doesnt seem to change anything.
i get site 1,2,3,4 but no others and since it isnt affiliating i have to get it to the site thats closest to me at the time.
any one know whats wrong or any ideas.
any help would be great.
thanks

I am worried that you made a mistake in your programming and are affiliating. First off I should mention that if you are using a MTS2000 you must be on a 3600 system, and I admit I don't know much about them - all I have learned is on 9600 P25 systems. Of the several "safe" ways to scan that I have learned about since this thread started - none of them display site information or let you site scan / force to other sites since the radios are not affiliating. You must be using the "hidden talkgroup method?" When I tested that method the RSSI/site search button had no function and would bonk when pressed - because you are not on a trunking TG. If you are set to anything other than a conventional channel be very careful. If you are seeing site information (you said you see site 1, 2, 3, and 4) I strongly suspect you are affiliating.

Jim202 is spot on, there is much danger involved in these scanning methods especially if you don't understand the system / net management side of the coin.

 

[Skypilot007]

This question comes up often and as you read through all the replies, you get the feeling that there are two positions. Those that say by inhibiting the transmitter, you prevent the radio from ever sending out it's ID. Then there are those that say you can't totally prevent the radio from ever transmitting. Actually, the second group is correct.

What hasn't been mentioned on any of the comments is that there is a command that the trunking systems have available that will cause any radio on the system to affiliate even though it has been programmed not to do it. This is a system command that many of the systems administrators use in managing their system. It finds boot legged radios on their system and they can then be killed or stunned. Which ever word you want to use, if your radio still has a transmitter in it, some time along the use of that radio, it will be requested to affiliate. When it does, you have been found out and action will be taken.

To those that want to bash these comments, it would be wise to learn how a trunking system functions before you start making statements that you can't back up. I am not taking a position one way or the other, but just passing along some important facts that most of you don't know about. Now you can go do as you please with your trunking radios used for monitoring only.

What is your trunking system coverage type set too? This will determine what you can and cannot do with different sites on the system. The radio will follow the the system, use the strongest site and never affiliate if you program it properly. Just like a multisite trunking scanner would.

 

[ElroyJetson]

The hidden talkgroups method of scanning is proven safe if properly implemented.

What is the hidden talkgroups method, you ask?

It's something I came up with several years ago.

You can scan trunked talkgroups from a scan list slaved to a CONVENTIONAL personality.

Now, create your trunked talkgroups and assign them so that they all occur ONLY above channel 16 in the zone/channel assignment page.

Do NOT have a CHANNEL menu selection in your radio.

Only conventional channels get assigned to the first 16 positions in any zone.

With no channel menu programmed, you will thus NOT be able to access any channel above channel number 16 in any zone.

The trunked personalities are programmed only into channel (or sub) slots 17 and above.

The trunked personalities are referenced in scan lists that are referenced only from your conventional
personalities.

When you are then on your conventional personality, found on any given channel that can be accessed via the 16 position channel knob, and enable scan, then the trunked personalities that are chosen are scanned....from a conventional channel's scan list.

It's completely "safe" if implemented as described. NO radio will affiliate if it's only scanning the talkgroups and the radio's selected channel is conventional and not trunked.

And, for additional safety, set trunked personalities to low power and use the tuner to adjust low power
output to the absolute minimum setting. This is about -60 dBm on an XTX5000, or just one billionth of
a watt. Finally, set tx deviation to zero.

The transmitter range at this power level is measured in feet. With no deviation, the system can't even
figure out your ID even if you are in transmitter range, which would be within spitting distance of the tower,
practically. And it won't transmit anyway when only scanning trunked talkgroups from a conventional channel.

Enable hardware encryption and select secure TX only as well.

And set the time out timer to the minimum setting, which I think is one second.

You can't get any safer than that on an 800 MHz system.

On an other band system, VHF or UHF, simply enter an incorrect TX offset and then any transmissions
that manage to make it through all the other roadblocks I just described won't even be heard by the system anyway. This is as safe as it gets short of removing the transmit PA and driver from the radio.


Elroy

 

[ElroyJetson]

Another thing about it is that if you don't have a channel menu in the radio, you can't even directly access any trunked personalities if they're kept above channel/sub 16. Turn scan off and nobody can find your trunked talkgroups in any zone on any channel they can access. (Also, don't have a VIEW menu enabled so nobody can look at your scan list.)

Safe scanning with a Moto radio is indeed possible. You just have to think about how many ways you can screw up the personality with regard to buggering the transmit capability.

The answer is, A LOT.

And, I've also successfully scanned digital trunked systems using ONLY conventional channels. This works OK if the system isn't very busy. If there's only one conversation going on in the entire system, scanning in conventional channels is just about as good as trunking scan. This works well for many .gov trunked systems because they're generally not very busy. It also eliminates any need to mess with that legally tricky issue regarding system key or equivalent access.




Elroy

 

[exkalibur]

Jim;

You're correct you can have the radio force affiliate via "snapshot" in System Watch and whatever else.

However, the TX Inhibit option WILL prevent the radio from responding to said request.

This has been tested on an 800MHz and a VHF SmartZone system. It works. There is NOTHING that can be done to make a radio set to transmit so long as it is set in the TX Inhibit mode. This was asked at a Motorola SmartZone training class in Schaumberg and their engineering staff confirmed that the TX Inhibit mode prevents the radio from EVER transmitting, end of story.

 

[grem467]

Keep in mind that if the admin knows the ID to the point of forcing the radio to affiliate, they also know the ID to send the inhibit command. This command WILL be successful even if the radio does not inform the system otherwise.

 

[exkalibur]

Just program the RID to be 0 and you're golden. Yes, this can be done on anything newer than an APX.

 

[mikewazowski]

Yes, this can be done on anything newer than an APX.

I didn't know there was anything newer then the APX

 

[N4DES]

Just program the RID to be 0 and you're golden. Yes, this can be done on anything newer than an APX.

ID of zero (0) is not valid in a Motorola radio. It will give you an invalid field report.

 

[N4DES]

Keep in mind that if the admin knows the ID to the point of forcing the radio to affiliate, they also know the ID to send the inhibit command. This command WILL be successful even if the radio does not inform the system otherwise.

Yep..Been on the giving end of that command a number of times. :roll:

 

[exkalibur]

ID of zero (0) is not valid in a Motorola radio. It will give you an invalid field report.

Some radios (GTX and Maxtrac, for example) will let you program 700000 as the RID right "out of the box". Other radios require some tweaking. However, it can be done.

 

[MTS2000des]

I gotta throw my 2 cents in here too.... I would agree with most of the guys on here in saying that programming a Motorola 2way to receive trunked radio data/communications is not a good idea. Not to mention even if you did crunch all of this data into the radio...system keys ect.. And if a cop seen you with a portable radio that receives there radio traffic, would more than likely land you in some serious trouble. More so if you have a radio on an astro25 network. Plus it could be potentially dangerous if it somehow ended up in the wrong hands, Even if it was programmed to only receive. I'd stick with a good trunking scanner, while I would agree that an actual Motorola radio has much better audio, You can get external speakers to plug into your scanner to get better audio. As far as a Motorola radio "receiving" better than a scanner, essentially the police scanner is specifically designed to receive audio/data for specific radio systems (as is the radio it's self) So yet again...stick with a scanner

There is no way to send an inhibit command to a scanner.
No system key, illegally obtained software, or private information is needed to program a scanner.
No one has ever been charged with a computer crime for the mere act of programming a scanner. (Not the case with trunking radios)
A scanner cannot affiliate, or attempt to affiliate, with any radio system because it doesn't have a transmitter.

Buy a scanner, stay out of trouble, enjoy.

 

[SCPD]

I keep checking this thread as new posts are added hoping to find new information or an insightful post, only to find the stinky carcass of a dead horse being kicked in the middle of the night.

Please, for the love of everything sensible, can someone close this thread?

 

[bezking]

I keep checking this thread as new posts are added hoping to find new information or an insightful post, only to find the stinky carcass of a dead horse being kicked in the middle of the night.

Please, for the love of everything sensible, can someone close this thread?

We seem to be getting there...

Guys, this is your last warning. If you keep taking this thread off topic, I will issue infractions (not warnings) for anybody who does not comply and close this thread.

RR is NOT the place to discuss the legalities of monitoring a TRS with an /\/\ radio, and we do not need any more "here's why this isn't a good idea" posts.

Look, here's what I tell people in real life about doing this: If you had to ask here how to do this, you aren't qualified to do it. That's all. Let's keep this thread a technical discussion of the process by which a Moto radio or any other Trunked terminal can be modified or programmed to not affiliate or transmit on the target TRS.

Thanks guys.

 

[N4DES]

Some radios (GTX and Maxtrac, for example) will let you program 700000 as the RID right "out of the box". Other radios require some tweaking. However, it can be done.

99% of those who try will not be able to get there and the GTX and Maxtrac will not supported a rebanded system, so your statement is moot.

 

[GroundLoop]

For receive-only configurations on Smartnet/Smartzone, is the System Key file still needed?
Obviously scanners & UniTrunker don't need it.
Do the Mot radios need it to receive, or only to affiliate?

 

[bezking]

The CPS won't let you write the system into the radio (regardless of what you want to do) without the System key.

 

[rescue161]

A System Key file is not used to monitor the system. It is only used to program a Motorola radio onto a trunking system. Like bezking said, the CPS nor the RSS will allow you to even get to the appropriate areas to program what you want without that system key.

 

[GroundLoop]

So the RSS/CPS program itself checks the System Key? I thought it had some critical system parameters, not just an 'unlock code' for the PC software to check.
Is the file not included in the onboard radio programming at all?

This would imply that if you used some software other than RSS to program the radio, it wouldn't be needed?

 

[bezking]

Basically, the only purpose of the System Key is to tell the CPS, "hey, this user is allowed to be on this system." It doesn't get sent to the radio and it's not needed for anything else.

While now /\/\ issues the keys on dongles, the original ones were just software files, and System Key file Generation is insanely easy.