RE: radio setups
Sort of. "ATV" is adjustable travel volume and "EPA" is end point adjustment. The first refers to the total arc of travel and the second refers to the adgustment of where the travel stops. You get more throw with a longer servo arm but more leverage with a longer control horn at the control surface. Best adjustment (IMHO) is to maximize the servo throw and adjust the control horn to suit. That gives you more sensitivity.