A RF receiver section for INMARSAT-C external mounting unit was designed, fabricated and evaluated. Using a INA-03184, the high gain amplifier consists of matched amplifier type. Active bias circuitry can be used to provide temperature stability without requiring the large voltage drop or relatively high-dissipated power needed with a bias stabilization resistor. The bandpass filter was used to reduce a spurious level. As a result, the characteristics of the receiver section implemented here show 60 dB in gain, 44.83 dBc in a spurious level. The voltage standing wave ratios(VSWR)of input output port are less than 1.8:1, respectively.