A folding, portable radio device is provided, which optimizes the gain characteristic of an antenna optionally. This device comprises (a) a first package; (b) a second package connected pivotably to the first package around a specific axis with a joint; the second package being able to be held at a desired angle with respect to the first package; (c) an antenna attached to the second package; (d) a third package connected pivotably to the first package around the axis with the joint; the third package being adjacent to the first package; the third package being abcle to be held at a desired angle with respect to the first package; and (e) a radio section mounted on at least one of the first, second, and third packages. Preferably, the joint comprises a first pivot limiter for defining the maximum angle of the second package and a second pivot limiter for defining the maximum angle of the third package.