Abstract:
Problems of the development of high frequency amplifiers begin when we attempt to reach frequency 30MHz and above. They exist because of presence of input capacitance in the amplifying element. There is no element with the zero capacitance. When frequency is growing up, reactance is coming down. It decreases input and output signals respectively. Until now as an amplifying element we used a bipolar transistor. When we have started using FET transistor many problems have been solved.