The Application of Designed Experiments to the Card Translator

In order to permit circuit designers to use the full capabilities of card translators 1 it has been necessary to conduct tests to determine (1) the time intervals required to drop the cards into reading positions and (2) the maximum number of cards which a translator can operate reliably. It was also desired to establish the maximum and minimum number of cards t h a t could be operated efficiently in a card translator. Early estimates indicated a machine capacity of 1,000 cards but if a higher capacity could be demonstrated, a considerable cost saving in the 4A system would result. Since some differences in card drop time known to exist are due to card position and machine loading this study also was to consider whether or not any special loading instructions were necessary or desirable for field use of card translators. As the study commenced the Western Electric Company Installation D e p a r t m e n t requested information as to the need for leveling card translators on installation and it was felt t h a t such information could readily be obtained in the course of this study. In investigating the effect of the m a n y variables related to card drop time, a consideration was given to the possibility of the need for any design changes. 369