236 THE BELL SYSTEM TECHNICAL JOURNAL, APRIL 1951 



ucts many other important applications. One indication of this ramification 

 is the widespread use of the "db", the unit which was originally adopted 

 for telephone transmission work. 



While this evolution in technology, which has been outlined here, has 

 been presented in its application to the telephone transmitter and receiver, 

 it is in keeping generally with the progress of the technology of the times. 

 To expand a previous statement, this apphcation has claims to distinction 

 in the degree to which it has been necessary to go in measuring subjective 

 performance, and in the degree to which it has been possible to go in inte- 

 grating the dictates of the laboratory, factory and field in making "design 

 for service" approach its goal of maximum ratio of service to cost. 



Although only a few have been named here, many have taken part in 

 this evolution in technology. These many are collaborators in this anniver- 

 sary article and in furthering Bell's vision of the "grand system." 



Bibliography 



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Tech. Jour., V. 3, April 1924, pp. 232 to 237. 



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