c62 c63 c64 and c65 inductor l1 and microstrip line circuit sl3 and sl5 the output signal from low pass filter 11 is then sent to radio frequency amplifier 12 for amplification radio frequency amplifier 12 consists of coupling capacitor c66 transistor q1 diode d1 bias resistors r49 r50 and r51 ground capacitor c67 decoupling circuit r52 and c69 and microstrip line circuit sl7 the amplified signal from radio frequency amplifier 12 is then sent to frequency converter 2 through capacitor c70 and diode d4 decoupling circuit r52 and c69 of radio frequency amplifier 12 prohibits high frequency signal from passing through resistor r53 to diode d4 similarly when a b terminal option switch sw1 of switching circuit 13 is at low potential transistor q3 and diode d3 are electrically connected transistor q2 and diode d4 are electrically disconnected and therefore radio signal is inputted into radio frequency input device 1 through terminal b and then sent to low pass filter 11 39 which consists of capacitors c43 c45 c46 c47 c48 and c49 inductor l12 and microstrip line circuit sl4 and sl6 permitting frequency over 2050 mhz to be removed and impedance matched the output signal from low pass filter 11 39 is then sent to radio frequency amplifier 12 39 for amplification which radio frequency amplifier 12 39 consists of coupling capacitor c52 transistor q4 diode d2 bias resistors r39 r41 and r43 ground capacitor c53 decoupling circuit r42 and c54 and microstrip line circuit sl8 the amplified output signal from radio amplifier 12 39 is then sent to frequency converter 2 through capacitor c71 and diode.