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BELL SYSTEM TECHNICAL JOURNAL 



Fig. 10 — Effect of transmitting dark current 14 db below maximum. 

 (Compare with Fig. 9.) 



SENT SIGNAL 



RESULTANT 



T^ ^ — 



k / TIME \ 



UN ^ '- 



PHASE / 



/'QUADRATURE 



Fig. 11 — Effect of shortening dots. (Compare with Fig. 9.) 



SENT SIGNAL 



/.''quadrature 



Fig. 12 — Effect of adding dark current with shortened dots. 

 (Compare with Figs. 11 and 10.) 



and similar figures is principally on the outside of dots rather than on 

 the inside. This tendency of the quadrature component to disappear 

 when very short marks are employed, accounts for the observed fact 

 that fine details are separated with single sideband methods as well 

 as with double sideband methods using twice the bandwidth. Thirdly, 

 the figures illustrate the effect of having finite dark current. This 



