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BELL SYSTEM TECHNICAL JOURNAL 



remembering, of course, that cr(aj) is to be negative. On the other 

 hand, a consideration of the nature of the phase variation, </)(a)), of 

 the lattice network as compared to the distortion of the cable phase 



2 4 6 



8 10 12 14 16 18 20 22 34 26 28 30 32 34 36 38 40 

 FREQUENCY IN HUNDRED CYCLES PER SECOND 



Fig. 17 — Phase distortion correction on 25 miles of 19 gauge H-44-25 loaded cable 



2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 

 FREQUENCY IN HUNDRED CYCLES PER SECOND 



Fig. 18 — Phase distortion correction on 25 mile 19-gauge H-44-25 cable 



corresponding to various values of t, leads to a choice of t such that 

 approximately the maximum cable distortion occurs at a frequency- 

 somewhat below the upper frequency of the essential range (Figs. 17 

 and 18). 



