1098 THE BELL SYSTEM TECHNICAL JOURNAL, SEPTEMBER 1953 



aligning the various components. With fixtures of this kind virtually all 

 assembly can be made without resorting to measurements. The design 

 of the translator and the fixtures were, therefore, carried forward con- 

 currently. 



An initial step in fabricating the card translator with the aid of these 

 fixtures is illustrated in Fig. 41, in which the basic surface plate is shown 

 mounted on the base casting. Fig. 42 shows another step in the fabrica- 

 tion of a translator. It will be noted that in this instance a supplementary 

 fixture had been added which supports the card cage and the pull-up 

 magnet superstructure. Later the side frames are added and these too 

 are located by means of the fixtures as is indicated by Fig. 43. It will be 

 understood that many additional fixtures are used in completing the job 

 and that one of the most important of these is a fixture which locates 

 the gates in which the phototransistors are mounted. However, by the 

 time this fixture is used, the assembly has built up to a point where the 

 fixture used is obscured by the side frames and other details. This method 

 of construction has proved to be very effective as is evidenced by the 

 fact that after assembly there have been no cases where the performance 

 requirements could not be met readily because of misalignment of com- 

 ponents. 



The development of nationwide dialing is the result of close coopera- 

 tion of many people in the American Telephone and Telegraph Company, 

 the associated Telephone Companies and particularly for the card trans- 

 lator, the Western Electric Company, as well as of many people in Bell 

 Telephone Laboratories. All who have had a part in this development, 

 which may justifiably be considered a milestone in the development of 

 the switching art, can view with pride their accomplishments. This 

 development, serving as the means for connecting on a nationwide basis 

 all the customers' lines into one vast automatic switching network, is 

 truly a major contribution to the telephone art. 



