Design method of multistage amplifiers using nichols chart

A method for the graphical analysis of various characteristic quantities of active two-port networks, using the Nichols chart, is given. A method of graphically designing high-frequency multistage amplifers using this graphical analysis method is described. The multistage amplifiers can be designed in the same way if any one of three stability factors (invariant stability factor, Stern´s stability factor and performance factor) is specified. One can design these amplifiers using only two charts (the Nichols chart and the auxiliary curves overlay) without using many graphs. This method is very convenient in the design of multistage amplifiers using potentially unstable active elements.