394 



THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1954 



Table XV — Card Translator — Summary of Data on Card 

 Rebound — Card Support Bars Out 



No. of operations 200 



No. of operations with no rebound 83 



No. of operations with one rebound 116 



No. of operations with two rebounds 1 



Maximum duration of one rel)Ound 17 ms. 



Minimum duration of one rebound 6 ms. 



Duration of two rebounds 28 ms. 



Ma.ximum magnitude of a rebound J^^ reopening 



100% 

 41.5% 

 58% 

 0.5% 



translators. The effect of the load in the machine was fm'ther inves- 

 tigated in the balanced vs. unl)alaiiced loading test and although it was 

 found that a balanced load produced a faster drop time, the amotmt 

 of improvement obtained by balancing the load is not enough to warrant 

 special loading instructions. 



The cai'd dropping time as observed with the card support bars otit of 

 the circuit ranged from 10 to 40 ms with a mean of 2(i.7 ms and the 

 predicted total range is from 1 to 52 ms. Although the minimum dropping 

 time is considerably less with the card support bars out, the translator 

 cannot l)e operated satisfactoiily in this manner. The cards rebound on 

 a majority of the operations; in fact, 58 per cent of the operations with 

 the card sujjport bars out had measiu'able reboimd. When operated in 

 the normal maimer no card reboiuid was observed at any time. A sum- 

 mary of the amoimt of card rebound observed is given in Table XV. 



As a result of this study, it was concluded that the recjuirement for 

 minimum 05 cards per bin should be remo\'ed and that the field be 

 permitted to place as few cards as they find convenient in any bin. A 

 second conclusion was that the maximum number of cards per bin beset 

 at 100. This will allow a total of 1,200 cards per machine, an increase of 



