On the Futaba radio you can program it so you choose the position on the throttle stick which activates the mix. On mine, if the stick is all the way down (idle), then it mixes in a certain percent of down elevator. If the stick is one click higher than idle, there is no throttle to elevator mixing. This is done with the Airbrake function on the transmitter. I also use a switch to turn the mix off for landing.