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BELL SYSTEM TECHNICAL JOURNAL 



spacing bias and marking "end distortion" (SB and ME displacements). 

 The arrow U b and U e show the upper limits or orientation with, respec- 

 tively, marking bias and spacing "end distortion" (MB and SE dis- 

 placements). 



Figure 6(A) shows the case of positive internal bias and positive skew; 

 Fig. 6(B), positive bias and negative skew; Fig. 6(C), negative bias and posi- 



START I 2 



-*»Ue 



-•>UB 





SE 



ME MBkJ-: 



(A) 

 + BIAS +SKEW 



Hb' 



^ 



"1 



-Lc 



SB 



■*^f 



SEi^ 



— Ub 

 ■*Le 



\Mf MBi 



CB) 

 + BIAS -SKEW 



~L 



►Ur 



— ^Lb 



_LL"i=^ SB SE IME 



^ (C) 



-BIAS +SKEW 



-*-^B 





s^£|^= 



"I 



_jSB SEi< 





-*Le 



h^ 



-MiET" 



A 



(D) 

 -BIAS -SKEW 



Fig. 6 — Use of distorted test signals in measuring inte nal distortion. 



tive skew; and Fig. 6(D), negative bias and negative skew. The following 

 relationships hold, bearing in mind that MB = SB = SE = ME = D: 



Fig. Eias Skew Lb Ub Le Ue 



(A) -I- -I- D+s-b l-b-s-D D 1-Z» 



(B) + - D-h i-b-D D+(-s) ].-(-s)-D 



(C) - + D+s+i-b) l+(-b)-s-D D 1-D 



(D) - - D+(-b) l + (-b)-D D+(-s) l-(-s)-D 



