Have you tried taking your 785 mobile? Maybe go someplace that has a known system. Maybe roll up towards Turlock or even Sacto and see if you can get those systems to work. You will hear things that sound like trunking control channels throughout the bands, however not all will in fact be trunked systems. There are many other data formats which will sound like the famous chainsaw. Try searching the other bands too i.e. 405-420, 450-455, 460-465, 482-493, 851-869, and 935-940MHz. I find systems through most of these bands in most areas, so don't limit yourself to just 800.