RE: Art-Tech Shark 450
it's on "the function list" and allows you to select a switch to control it, mine is set to use Aux2 on the heli tx. the plank tx I'm not sure as the 2 DX7's that I have are both the heli tx's and the switching is different plank to heli. All of the setting paramaters are described in the manual with the options available to select. To learn all the functions available to you, you'd better take at least half a year off and study the manual in extreme detail, there are that many.
battery slot