A very simple and useful antenna amplifier can be constructed using this circuit diagram . This antenna amplifier is very useful for 35kHz-150Mhz frequency band . This antenna amplifier circuit is based on transistors and has a low 3 dB non-linearity and a high gain of 43 dB . The input and output impedance for this rf amplifier is 75 ohms . The L1 and L2 radio frequency coils are constructed from a 0.25 mm CuEm wire , with a 5 mm diameter . Both coils require 10 number of turns .
All used transistors are of the same type and can be BF183, BF200 or other similar type . The total consumption of this rf amplifier is very low , the circuit will need only 20 mA .
This rf amplifier circuit needs to be powered from a 12.5 volts DC power supply circuit .