| 摘要 |
PURPOSE:To reduce the occurrence of the dispersion in the performance by connecting a gate electrode of a FET for the low noise amplifier to an input probe provided on a dielectric substrate with an interval therefrom. CONSTITUTION:A FET 30 is fitted onto a dielectric base 40. An input probe 41 to which an antenna output is led is provided on the substrate 40 with an interval from the arranged location of the FET 30. Since a long gate electrode 3G of the FET 30 is used for an input lead, and the length of the gate electrode 3G and the distance thereof from the substrate 40 are formed in advance and the tip is soldered to the probe 41 so as to obtain an impedance minimizing a noise figure of the FET 30. Furthermore, when the electrode 3G is parted from the substrate 40, a long hole 42 is formed on the substrate opposite to the electrode 3G shown in figure B. Then a dielectric loss is eliminated and the characteristic impedance of the lead part is increased and the adjustment to obtain the optimum matching is facilitated. |
