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THE BELL SYSTEM TECHNICAL JOURNAL, MAY 1952 



the relevant part of it between A-A and D-D) obtains from Fig. 5 by 

 inserting ideal branches — two poles — across each terminal pair of each 

 box, and neglecting the outlines of the boxes. The upper m channels of 

 this ideal graph are then T sections, and the lower n-ni are degenerate T 

 sections with no shunt arm. This ideal graph is shown in Fig. 6. The 

 ideal branches are shown as small boxes. 



The program of the next few paragraphs is to demonstrate that Mad 

 is a physically realizable 2(2M)-pole. 



4.54 Let us designate the terminal pairs of Mad on the section A-A by 

 Ti , Ti , • • • ; Tn , Tn , where the r* pair is the intersection with A-A 

 of the leads to the r^^ terminal pair of N. We designate the pairs on 



rz 

 rz 

 rz 



r 



A '^ B 



Fig. 5 — Original form for N 



C ^^ D ^'"' 



B C 



Fig. 6 — Ideal graph of Mad 



