they are tuned to cover the full range of both airwave and the 305 stuff like hobbyking centering on the middle of the bands used
305
5705,5865,5665,5645,5885,5905,5925,5945
airwave
5740, 5760, 5780, 5800, 5820, 5840, 5860
the center of that is 5800-5815