| 摘要 |
PURPOSE:To realize size reduction and reduce the coupling between a UHF circuit and a VHF circuit, to simplify a switching circuit, and to perform IC- implementation suitably by uniting a UHF mixer and a VHF mixer. CONSTITUTION:Local oscillation signals which are opposite in phase with each other are inputted from a 3rd terminal 23 and a 4th terminal 24 and when a 1st frequency band signal is inputted from a 1st high frequency input terminal 25 by turning on a 1st switching circuit 47, a 1st field effect transistor FET 15 and a 2nd FET 16 are made to operate as a single balance mixer, thereby leading out an intermediate frequency of the sum of difference frequency of a signal of a 1st band and the local oscillation signal from a 5th terminal 31 and a 6th terminal 32. When a 2nd frequency band signal is inputted from a 2nd high frequency input terminal 26 by turning on a 2nd switching circuit 48, a 3rd FET 17 and a 4th FET 18 are made to operate as a single balance mixer, thereby leading out an intermediate frequency signal of the difference or sum frequency of a signal of a 2nd band and the local oscillation signal from a 5th terminal 31 and a 6th terminal 32.
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