446 BELL SYSTEM TECHNICAL JOURNAL 



line would have if non-dissipative, is supplemented with an excess- 

 simulator such as to simulate the excess impedance of the actual line. 



Since the excess impedance depends somewhat on the relative 

 termination it can be simulated more easily at certain relative termi- 

 nations than at others. This fact is utilized in the arrangement 

 represented by Fig. lid. Here the basic network is built-out to 

 some relati\e termination that is particularly favorable for the design 

 of an excess-simulator; the excess-simulator is applied; and then is 

 applied the building-out structure, which for the highest precision 

 must be dissipative to correspond to the actual line. 



The simulation-range of the basic networks described in this paper 

 is a little less than the first transmitting band of the loaded line; but 

 after a basic network has been built-out, its simulation-range may 

 extend a little way into the succeeding attenuating band, omitting 

 the immediate neighborhood of the critical frequency. The com- 

 pensation-range of the compensating-networks is somewhat less than 

 the first transmitting band of the loaded line. 



PART \' 



Networks for Xox-Dissip.xtive I.o.mjed Lines without 



DiSTRIRUTED InDUCT.VNCE 



In this Part will be described a considerable number of kinds of 

 "basic networks" for simulating the characteristic impedance of non- 

 dissipative loaded lines without distributed inductance; and two 

 types of compensating networks for such lines. The modifications 

 necessary when the lines have small distributed inductance will be 

 indicated in Part \'I. 



The various kinds of basic networks here described ma>' be regarded 

 as of two different types corresponding to the terminations of the 

 loaded lines to which the>' pertain; there ma\' be se\cral \arieties of 

 each type. The two t>'pes correspond to fractional-section and to 

 fractional-load terminations rcspectixely; that is, to the relative termi- 

 nations Ok and (Ti resi>ectively. (It has been stated already, in Part 

 IV, that Oh and <Jb' lie between about 0.1 and about 0.2.) It 

 will ajijiear below that these two types are inverse types, in the sense 

 that the impedance of a network of one type is of the same functional 

 form as the admittance of the corresjionding network of the other 

 type, when the frequency is regarded as the independent variable. 

 In particular, for equal relative terminations {ab = ab'), the ratio 

 of the impedance and the admittance of any two corresponding 

 inverse networks is indepeiulent of frequency. This corresponds to 

 the relations Z/W' = \ and Z'/W=\, holding for the loaded line 



