Not aware of any designation in Sentinel. I bring up the RR database in a split screen, and then delete the channels I don't need. I suggest programming all of the active control channels for your chosen sites as conventional channels into a separate favorites list. This will allow you to "walk through" your control channels every day or two. If any are missing, it tells you there has been a change of control channel for the site. The separate favorites list also allows you to determine which sites are providing the strongest signal at your location. Using quick keys, you can "lock out" the sites you don't need, allowing even faster scanning. I've read that the BCD436HP and BCD536HP do not automatically select the strongest site. Some of the reviews indicate that the Whistler TRX-1 does select the strongest site, but there are complex settings that you have to tinker with. I've been trying for nearly a month to get my TRX-1 to select the best signal from the Oswald Dome, North Bradley, and Chattanooga Simulcast sites, and I'm not yet satisfied with my programming. Still working on this project.