A sensor signal comprising a first signal pulse having a first voltage amplitude and a second signal pulse having a second voltage amplitude greater than or substantially equal to the first voltage amplitude is obtained from a sensor positioned adjacent a feedback device coupled to rotate with an aircraft-bladed rotor about a longitudinal axis and to move along the axis with adjustment of the rotor's blade pitch angle. The feedback device comprises a reference feature configured to generate the second signal pulse and varying detectable feature(s) configured to generate the first signal pulse and to cause a change in the first voltage amplitude as a function of an axial position of the feedback device along the axis. A voltage ratio is determined based on the first voltage amplitude and the second voltage amplitude, and the axial position of the feedback device is determined from the voltage ratio.