CARRIER TELEGRAPH METHODS 



495 



SIGNAL SPEED IN DOTS PER SECOND 

 35 40 45 50 55 



90 100 no 120 130 140 150 



SIGNAL SPEED IN WORDS PER MINUTE 



Fig. 3 — Distortion vs. speed characteristics of normal-band frequencj'-shift 

 arrangements, using two different types of modulator. 



