Unitrunker & UHF motorola question

[Airdorn]

Man, I'm having a blast with Unitrunker and a BCD996T!

A quick question though:

With the usual 800Mhz standard motorola system, as soon as a good control signal is presented to the Unitrunker program, the site ID appears and all the various frequencies appear on the left side of the screen, with the control channel in red.

I programmed a UHF Motorola type 2 system today, and it's a little weak (about 50% - 85%), but decoding still occurs.

But I noticed on the left side where the frequencies usually appear, instead, there are numbers like 29, 380, 441, 457, etc.... listed down the screen just like how the frequencies are. What are those?

Is that the frequency offsets or something? If so, how do I use those to derive real frequencies?

Thanks!

 

[rescue161]

Those are the numbers assigned as frequencies, because UniTrunker doesn't know what the base/offset is for that system. There are formulas for you to figure it out. Once you know, say the CC, then you use the formula and those numbers to figure out the rest of the channels. See the attached Word doc created by Wayne_H.

 

[Forts]

As mentioned those numbers are the channel #'s on the system basically, but since Unitrunker doesn't know the bandplan that's in use that's what you get. It may look a little daunting to figure out what the frequencies actually are, but it isn't that bad. Plus, if you have a second scanner you can use that to help you verify your results. Say one of your #'s calculates to 425.1250. Park your 2nd scanner on this frequency, then see if there is activity on that channel when it lights up in Unitrunker. You could also search thru a small range around the control channel frequency to help find other frequencies that way. It gets really fun when you find a system that has more than one base and offset frequency in use