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BELL SYSTEM TECHNICAL JOURNAL 



multiplied by the probability that exactly n stations will give a voltage 

 equal to or greater than x equals the probabi'ity of obtaining a voltage 

 equal to or greater than x from just n stations. 



Hence the summation from n = 1 tow=iV— lof these proba- 

 bilities for a given value of x will give the probability of obtaining a 



01 23456789 10 



TOTAL PEAK VOLTAGE 



Fig. 21 — Voltages resulting from several unit voltages each applied 15 per cent of 

 the time and with random phase and frequency 



voltage equal to or greater than x from all of the N stations in the 

 restricted frequency range considered or 



■ixN / / -t n-t a-' 



(403) 



In a vacuum tube large negative voltages are equally as important as 

 large positive voltages in producing distortion. Equation (403) has 



