To manufacture an antenna capable of reducing the length in a longitudinal direction by more than 1/4 wavelength of a signal which is to be received by winding a conductor around a base member, formed integrally by extruding forming.

A thin and long base member 20, made of an insulating material is formed with two halves that can be freely overlapped by a hinge 22, irregularities parts 26, 26 meshing with each other on press contact faces of the halves 24, 24 are provided in parallel with each other in the longitudinal direction, and plural gaps are formed in parallel in the longitudinal direction, because the projections do not reach the bottoms of the recessed parts. Each conductor is positioned by the projections 24, 24,... and penetrated through the air gaps 22, 22, folded at an end of the base member 20 and wound in parallel in the longitudinal direction, one end of each conductor 14 is led out of one end of the base member to form an antenna output terminal, and the other end is placed at or led from the other end of the base member 20, thus constituting the antenna.