ORIGINAL: LNEWQBAN
However, potentiometer is not related to the Tx, but to the servos.
Half true.....
In fact, the Tx's sticks have potentiometers attached to them that interpret the stick's movements. There is a pot for each axis so each stick has two pots connected.
The pots in the TX take the stick input and convert it (in one direction) just as the pots in the servos convert that information (in the opposite direction) into servo arm movement.