sentences:  It functioned as a crude modulator; it interrupted the signal from the detector at an audio rate, producing a buzz in the earphone whenever the carrier was present.Thus the "dots" and "dashes" of the Morse code were made audible.Around 1915 the tikker was replaced by a better means of accomplishing the same thing; the "heterodyne receiver" invented by Reginald Fessenden in 1902.