Abstract: In an electronic device, a pivot member of a cam follower unit is coupled pivotally to a retractable antenna assembly that is operable so as to move relative to a casing from a retracted position, where the antenna assembly is retracted into the casing, to an extended position, where the antenna assembly extends outwardly of the casing in a first direction. A cam groove unit is formed in the casing, and permits movement of the pivot member therealong such that the antenna assembly is able to move in the first direction from the retracted position to the extended position or in a second direction opposite to the first direction from the extended position to the retracted position. A biasing member is connected to the casing and the antenna assembly for biasing the antenna assembly in the first direction.