| 摘要 |
PURPOSE:To reduce noise, to increase a gain, and to decrease small gain deviation by providing two input signal terminals for the UHF band and VHF band without using a mixer which mixes a signal of the UHF band and a signal of the VHF band including the CATV broadcasting band with each other. CONSTITUTION:An input filter 5 consists of a filter group of filters corresponding to the 1st - the 4th divided bands of a band of 50-900MHz; and one of power terminals corresponding to the 1st - the 4th bands is selected to select one of the 1st - the 4th bands according to an applied voltage and part of an RF signal inputted from an input terminal 2 which corresponds to the necessary band is outputted from an output terminal 11. When a voltage is applied to a power terminal 6, a switching circuit 4 turns on and a signal of the UHF band inputted from an input terminal 1 is outputted from an output terminal 11 through a balun 3 and the switching circuit 4 and the signal from the input terminal 2 is cut off by the input filter 5 at this time.
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