Hey all i need to clear this up, cant every reciever support BEC?? Im asking b/c Im recieving a Futaba system free from a friend in a few weeks, and Its an older legacy system [its still such a nice system!] and i need to know if i need a speperate pack just to power it?? If the XL-5 is plugged into it, cant any reciever just run off the main battery?? Thx, i really need this cleared up!