604 



THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1951 



due to the fact that each jumper is threaded through a common array, of 

 ring-type induction coils with one coil for each digit in each place of the 

 output numbering scheme, that is, 44, as shown in Fig. 7. 



After the equipment number selection has been made, a surge of current 

 is passed through the jumper. Since the jumper acts as a single turn primary 

 for all the coils through which it is threaded, a high voltage is induced in 



,^rG RP(20)x 



|<Jh_G(5) 1 



lVF(5) J 



A 



®' EQLJrPMENT 

 NUMBER 

 TERMINALS 



OFFICE (4) 



THOU (10) 



HUNDS (10) 



TENS (10) 



UNITS (to) 



DIGIT NUMBERS 



Fig. 7 — Ring-type translator. 



the high turn secondaries of these coils which causes the cold cathode tube 

 associated with each of these coils to "trigger" and place a mark on the 

 corresponding output code marking lead. The translation for any equip- 

 ment number is changed by simply threading the associated jumper through 

 different coils. 



Many jumpers may be threaded through the same coils. The jumpers 

 thus act as individual coding devices and the coils as a reading equipment 

 common to all coding elements. 



