An antenna device for a portable terminal, which allows a whip antenna and helical antenna of a terminal to be retracted and withdrawn along an extension from the terminal, while not causing them to protrude out of the terminal. The energy-depleted beam intersects with the primary beam in a tapered annular region in which the two beams destructively interfere, because their wave intensities are adjusted to be equal and their phases are adjusted to be opposite. The retaining device is disposed on the substrate so as to position the cable along the substrate in such a manner that the cable will not interfere with the attachment of the substrate to the vehicle body structure. A sub-bass generator connected to the outlet of the low frequency monaural amplifier. The falsework further includes an upwardly extending member that is selectively interengageable with the base member.