628 BELL SYSTEM TECHNICAL JOURNAL 



F' = probability of obtaining a greater returned current 



than /s from a cable section with near end equip- 

 ment. 



F{N, T) = lOlogiorL 4--"') 



Gc and gc = gains as defined herein. 



/ = current obtained in a particular case. 



/o = current sent into the line at the point of measurement. 



Ii = anti logio f ~ j = current for active return 



loss corresponding to /' from " Irregularities in 

 Loaded Telephone Circuits " by G. Crisson in the 

 October 1925 Bell System Technical Journal. 



Ii — anti logio f t^ ) — current for active return 



loss corresponding to 7" from paper referred to 



under 7i. 

 /s = current defined above under F'.' 



If = current defined under F{If) above. 



Ilk = I' (from paper referred to above) for the currents 



from the k th repeater section from the critical 



repeater. 

 I2k = I" (from paper referred to above) for the currents 



from the k th repeater section from the critical 



repeater. 

 ii and 12 = currents returned from particular active or passive 



return losses. 

 is = current returned from a particular pair of active or 



passive return losses in series. 



= antilog.o(^) 



it = total current returned from line with equipment. 



j = number of the loading section measured from the 



repeater at which the return loss is of interest. 

 Ki{x) = Bessel function of the second kind and order unity 



with argument x. 

 k = the number of the repeater or repeater section from 



the critical repeater, e.g., for the adjacent repeater 



section ^ = 1, for the next k = 2, etc. 



