Programmable mix

From RC Helicopter Wiki

A programmable mix is a function of a computer transmitter where a portion of one control input can be automatically applied to another input or channel.

One common usage is a rudder to throttle mix, where right rudder increases the throttle setting slightly, and left rudder decreases is slightly; this is to compensate for the extra power needed to yaw right.

Another usage is a pair of mixes (one aileron to elevator and one elevator to aileron) to correct swashplate timing.