The high frequency device null which uses the filter and this filter which use the resonance circuit and this resonance circuit which use variable inductance and this variable

摘要

PURPOSE:To widen the adjustment range of an inductance in the satellite broadcast reception tuner used for a television receiver and a video tape recorder or the like. CONSTITUTION:A series circuit or a parallel circuit comprising capacitors 9,12,16 and print patterns 10,13,17 is provided to either or both of an input filter circuit 2 and an inter-stage filter circuit. An adjustment air-core coil 15 whose lead connects to ground is provided in the vicinity of a curved part 13a of the pattern 13 and induction coupling is provided between the adjustment air-core coil and the curved part 13a of the pattern 13 to adjust the inductance of the print pattern 13.