COMMON CONTROL SWITCHING SYSTEMS 



1091 



with the same P. 01 loss but witli an increase of efficiencj' of 15 per cent. 

 The efficiency' rises from 41 to 56 per cent. 



EVOLITTION OF PRINCIPLE OF TRANSLATION 



These studies had considerable effect dh the trend of sj^stem design. 

 For example, it appeared that grouping subscriber lines on the con- 

 nectors in groups of more than 100 might result in some economy and 

 that other economies were possible if the limitations imposed by decimal 

 selections were avoided. 



However, a new invention, namely translation, was reciuired before 

 sy.stems could operate with large access switches and non-decimal selec- 

 tions. Translation is a mechanical rearrangement which permits con- 

 version of the decimal information received from the dial to non-decimal 

 forms for switch control and other purposes. When translation is made 

 changeable b}' some means such as cross-connections, it is the basis ot 

 much of the flexibility of common-control systems. Translation was first 

 proposed by E. C. Molina late in 1905. A patent application* for a 

 Translating and Selecting Syston was filed on .\pril 20, 19()(). 



6 8 10 12 14 



AVERAGE = (LOAD CARRIED) 



Fig. 2— Bypath system. 



Patent No. 1,083,456 issued to E. C. Molina, Jan. 6, 1916. 



