Help with new trunks

Status
Not open for further replies.

ssscarpone

Member
Joined
Dec 22, 2009
Messages
5
First of thank you for answering my questions ahead of time.

I just purchased a RS PRO-164 scanner with 800 mhz bnc antenna. I bought this for the sole purpose of monitoring 2-way motorola radios.

I am writing this to see if this is even possible with the current info I have.

The radios are Motorola mts 2000's
I was told they operate on 800mhz.
I did the signal stalker 10 feet from the radio and got a 917.50000 one time and a 766.50000 another time. I saved them and tried to listen on the channels... nothing. So I signal stalked again and now I pick up nothing.

So in a nutshell. What info do I need to try to extract from the communications company?
 

gmclam

Member
Premium Subscriber
Joined
Sep 15, 2006
Messages
6,341
Location
Fair Oaks, CA
The PRO-164 will monitor most analog transmission out there. Knowing the transmitting device is a small portion of the big picture. You believe that what you want to monitor is in the 800 MHz band. That's fine. Now if it is a "simple" or "simplex" setup, then you would tune to the same frequency as being output from the Motorola hand-held. But few agencies work that way.....

The next step is that the agency uses a repeater. Typically in the 800 MHz band the transmitter frequency is 45.000 MHz below the receiver frequency. The frequencies are licensed to the agency as a pair. So you might transmit on 821.1250 MHz and the repeater listens on that frequency and transmits on 866.1250 MHz (just an example). So you'd want your scanner set to 866.1250 MHz in this case.

Another type of system that is common these days is a "trunked radio system". Think of it as a PBX phone system over the radio. There might only be 10 incoming lines, but 100 extensions. In radio talk, there might be 10 frequencies used, but 100 "talkgroups". There are several types of these trunked systems out there, but only 3 currently supported by scanners (like the '164) - Motorola, LTR & EDACS.

If you know the CALL LETTERS of the agency you want to monitor, you could do a search in our DataBase here on RR and see what that reveals. Otherwise you need to know if the system is simplex, duplex, repeated, trunked or whatever. Depending on these answers, we can figure out the frequencies being used, and perhaps it is known if they are analog, digital or whatever.
 

ssscarpone

Member
Joined
Dec 22, 2009
Messages
5
Here is some more info.

I was told they are analog 900mhz. I get conflicting stories on if it is trunked or not.

When I asked to get more info.. They said the frequencies are propiertary and they dont want me using a scanner to listen to them. LOL
 

captclint

Mentor
Joined
Dec 31, 2005
Messages
2,452
Location
Mountaintop, PA
Last edited:

ssscarpone

Member
Joined
Dec 22, 2009
Messages
5
Ok I found it.

What if the license expired 9 years ago???

And the freqs are in the 150.000 opposed to the 900mhz like they claim.
 
Status
Not open for further replies.
Top