Tube with conducting strips on walls - has strips applied to flexible foil stuck on cardboard cylinder

Hollow tube for use as an aerial manufactured from a flat plastic or cardboard material and with conducting strips wrapped around the surface. The pattern of the strips is accurately dimensioned with the exact distance between each pair. The strips are first etched or pressed on to a flat flexible foil in one or more layers, either in relief or recessed, with the edge zones stuck down or clamped. Before sticking the foil on to the tube material, its surface is first roughened and then coated with an adhesive. Both sides of the flat tube material are covered with a foil and then rolled into its cylindrical shape.