THE DESIGN OF TETRODE TRANSISTOR AMPLIFIERS 



823 



and straight line are sections of the paral)oloid and plane through the 

 gradient line of the plane over 1, 0. 



A straightforward analysis indicates that the point in the L-M plane 

 \\ here the maximum of Po/Pi occurs is at 



L + jAI = 1 - 



CKgG 



(23) 



^\liere these quantities are defined as in (2), (3), and (4). The power gain 

 cit this optimum point is Kg times that obtained at 1, 0. One finds that 

 1 he maximum gain is only two times Pm/Pio even if C approaches unity 

 A\ hich corresponds to the marginal case of potential instability. 

 The analysis just described leads to the maximum values of power 



I gain and to the best terminating impedances. For many design problems 

 1 liese answers are a guide but one may prefer to use other than optimum 



' \alues for other compelling reasons. For such a case charts from which 



I one can get the pertinent quantities are very helpful. 



P^^IGUE lN^DEGRee3 



G2+jB2= YL+h22 



^22 — i'22n +jh22l 



Fig. 8 ■ — Gain and impedance chart. 



