THE OCCURRENCE AND EFFECT OF LOCKOUT 



271 



sent the two complete sets of data. In the case of Fig. 5 the solid line 

 was determined by the method of least squares, omitting the data of 

 group 10. This omission appears to be justified since these data are 

 consistent among themselves and yield a factor of proportionality 



2 3.5 



."; 2.0 



0.10 0.15 0.20 



CALCULATED PROBABILITY 



Fig. 6 — Observed releasing lockouts vs. calculated probability. 



which is consistent with the rest of the data, and since it is known that 

 many uncontrolled factors may influence the results of one particular 

 group of tests. In the case of Fig. 6 the solid line was obtained by 

 averaging the slopes and constant terms of the individual dotted lines. 

 Both sets of data indicate that about 0.9 lockout per hundred seconds 

 occurs when the calculated probability of occurrence is zero. This is 

 undoubtedly due to non-synchronous action of the suppressors, caused 

 by slight variations in sensitivity, changes in effective hangover caused 

 by changes in sensitivity and by occasional relay chatter. This con- 



