Of course try the DPS Region 3 frequencies first for CC or whatever is close. The use of the LVRRS is an additional system if needed for DPS...by law the trooper should have a SO radio in their vehicle. You will hear them identify with their DPS unit designator...somewhere in the RRDB or the Wiki is a better explanation, but it should be 3C???...the 3 for the region and the rest of the unit number is rank and other info. I know it's in here somewhere, I just can't find it tonight. When the units here in NTX operate on another system, it is always with their DPS designated number. That area may be a no man's land for the VHF P25 frequencies the DPS uses! It's lonely in that stretch of TX....