Unitrunker not picking up frequencies

[BadRobot]

Greetings, apologies for my 1st post being a call for help, but as is the way, this is usually how all good things start....

I've picked up a RTL2832U dongle last week, and have been looking for things (like you do) I've stumbled across the local bus company and its MPT1327 trunk system, and I'm attempting to get my head around decoding it by following this guide to get started, & I've come to a halt trying to get the frequencies to display.
As you can see, its logging station actions, but doesn't pick up the frequencies, and I'd be grateful for a little guidance to get me back on track.
Below are images of current setup & configs, any advice is welcome
Thanks, Rob.

UniTrunker configs http://i.imgur.com/5hWmp3l.png
SDR# config http://i.imgur.com/orbUVHH.png

 

[SCPD]

Hi Rob;

MPT1327 does not (generally) tell you how to map channel numbers to frequencies. There is a mathematical relationship between the two but it is up to the operators as to how that is configured.

Start with the control channel - hand-edit the frequency to match. You will have to dig around for the others.

If you are in the USA, search FCC database for licensed frequencies. Of course, check the RR DB too. Worst case is use the waterfall display in SDR# to see the voice channels and then methodically determine which ones are part of this system and correlates to which channel number. Watching the Site window Calls tab and the SDR# waterfall simultaneously will net you some results.

Once you know the frequencies and channel numbers - a bit of algebra will allow mapping one to the other.

This is essentially the same problem as mapping channel numbers to frequencies on Motorola VHF / UHF systems.

 

[ghosttang]

Hi Rob;

MPT1327 does not (generally) tell you how to map channel numbers to frequencies. There is a mathematical relationship between the two but it is up to the operators as to how that is configured.

Start with the control channel - hand-edit the frequency to match. You will have to dig around for the others.

If you are in the USA, search FCC database for licensed frequencies. Of course, check the RR DB too. Worst case is use the waterfall display in SDR# to see the voice channels and then methodically determine which ones are part of this system and correlates to which channel number. Watching the Site window Calls tab and the SDR# waterfall simultaneously will net you some results.

Once you know the frequencies and channel numbers - a bit of algebra will allow mapping one to the other.

This is essentially the same problem as mapping channel numbers to frequencies on Motorola VHF / UHF systems.

Oh,I've the same problem ,and I've no idea how to do yet.
Could you say that more simply please.