| 摘要 |
PURPOSE:To avoid the fluctuation in tuning condition of an antenna, by arranging a ground conductor along a pair of feeding lines to flow heating current to a heating conductor wire. CONSTITUTION:A rear window glass 1 is provided with a heating conductor wire group 2, to which a heating current flows through buses 4-6 and feeding lines 20, 21. The upper side of the wire group 2 is provided with an antenna wire group 7, and a reception output is introduced to a preamplifier 9 via a coaxial cable 16. In this case, the wires 20, 21 between the buses 4, 6 and a choke coil 10 are taken as two cores, one of the cores 20, 20a is used as feeding line and other 20b, 21 are used as ground wires, and one end of the ground wires is grounded to body. Thus, even if the feeding lines 20, 21 are drawn in any way, the impedance to ground potential is not varied. Then, the production of dip to the directivity and uneven reception level can not be caused, allowing to stable nondirectivity. |
