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BELL SYSTEM TECHNICAL JOURNAL 



Solutions developed in this way can be added together, since it is 

 apparent from the general relation upon which they are based that the 

 phase characteristic corresponding to the sum of two attenuation 



20K 



5uiok 



A 



0.1 



0.2 0.3 0.4 0.5 I 2 3 4 5 10 



X 

 fo 

 Fig. 4 — Phase characteristic corresponding to a discontinuity in attenuation. 



20 k 





< - 



DU 10k 



UJ Q 



kJ^ 



k4^ 



0.2 0.3 0.4 05 



_f_ 



fo 



Fig. 5 — Phase characteristic corresponding to an attenuation which is constant below 

 a prescribed frequency and has a constant slope above it. 



characteristics will be equal to the sum of the phase characteristics 

 corresponding to the two attenuation characteristics separately. We 

 can therefore combine elementary solutions to secure more complicated 



