| 摘要 |
PURPOSE:To prevent the transmission of higher harmonics of a local oscillation signal from an antenna terminal through a tuner shaft as spurious radiation, by forming a part of a turret type VHF tuner shaft as an insulation shaft. CONSTITUTION:Shafts parts 17b and 17c of a turret type VHF tuner shaft 17 are made of metal and a part 17a of the shaft is made of an insulator. Even if higher harmonics of a local oscillating signal are induced on the said metal shaft part 17c from a local oscillation coil 13c, since the higher harmonics are insulated and attenuated at the shaft part 17a, the higher harmonics can not be propagated on the said metal shaft parts 17b. Thus, the said spurious harmonics can be induced on an antenna input coil 13a provided near the said metal shaft part 17b and spurious radiation radiated from an antenna terminal (not shown) externally (mainly, UHF band) can be reduced. |
