| 摘要 |
PURPOSE:To decrease the number of adjustment stages by simplifying constitution by omitting one filter from a frequency converting circuit. CONSTITUTION:An input signal is supplied to a terminal 18 and then reaches one terminal of a coaxial line 13 through a band-pass filter 12. The output of a local oscillator 11, on the other hand, is supplied to one terminal 20 of a coaxial line 15. The other-end terminals of the coaxial lines 13 and 15 are connected together at a connection point 17 and then connected to a frequency mixer 16. When the side of the filter 12 is viewed from the connection point 17, the length of the coaxial line 13 is so set that its impedance is nearly infinite at a local oscillation frequency. When the side of the local oscillator 11 is viewed from the connection point 17, on the other hand, the length of the coaxial line 15 is so set that its impedance is nearly infinite at an input signal frequency. |
