MEASUREMENT OF TELEGRAPH TR.ANSMISSION 



185 



The values of F„ computed by solving these equations were plotted 

 on Fig. 30 and a curve was drawn through them. It will be under- 

 stood, that, on the scale of abscissae, F is the fundamental frequency 

 of the character and the coefficients of F are values of n. 



2F 



5F 



6F 



7F 



Fig. 



3F 4F 



FREQUENCY 



30 — Transfer admittance characteristic for undistorted transmission using 

 frequencies up to seven times the fundamental frequency of the character. 



By the methods employed in the previous paper ^ it can be shown 

 that, for signals employing the same permissible intervals between 

 transitions, the solutions of equations similar to the above approach 

 the smooth curve as a limit as the period of repetition is lengthened. 



These equations may be used to prove that when the six simple 

 characters are perfectly transmitted, all other teletypewriter signals 

 may be transmitted on a repeated basis. For distortionless transmis- 

 sion f(t) should equal 1/2 at each transition point, assuming that the 



