In facsimile, a frequency modulationsystem where one frequency represents picture black and another frequency represents picture white[?]. Frequencies between these two limits may represent shades of gray
An intentional frequency change used for modulation purposes
... the village. The population density is 380.6/km² (967.1/mi²). There are 595 housing units at an average density of 1,640.9/km² (4,169.6/mi²). The ...