TRANSLATORS AND IDENTIFIERS IN SWITCHING SYSTEMS 



603 



separate cross connections for each directory number, each connected to a 

 2-code passive coding element permanently associated with one marking 

 lead in each of two groups of output code bus bars, it was possible to effect 

 considerable economy over at least schemes like those shown in Figs. 4 

 and 5. 



HUNDS 



TENS 



UNITS 



1000 SETS 

 3 LEADS EACH 



000 



003 < 



999 < 





® \ \ TERMS 



OF 10 



\ 



\ 



DIRECTORY 

 NUMBER TERMS. 



\ HG&V^ VVV 



\ COMB. 

 \TERMS. 



VFi^^ VW , 



COMB. 

 TERMS. 



>-< 



TOl 

 OF 15 



— ^-M 2 



FU(IO) < 

 VG(7) >^ 



VF(IO) 

 _S(I52 



Fig. 6 — Number group translator for ^ 5 crossbar office. 



Ring Type Translator 



An example of a translator with still further simplification and improve- 

 ment of the coding equipment is that shown in Fig. 7, which is also used in 

 the ^ 5 Crossbar office, in this case for determining the directory number of 

 a calling station when the equipment location number is known and it is 

 desired to make a record of the caUing number for charging for the call. 

 This is the reverse translation of the case covered by Fig. 6. 



As used in practice, the translator of Fig. 7 is limited to capacity for 1000 

 mixed base input codes, any of which may be translated to any of 40,000 

 directory number output codes in a 5-place decimal system. 



Here the relay selection tree, under control of the input code, causes the 

 selection of a one-wire circuit to one out of 1000 equipment number terminals 

 each of which has a cross-connection wire which serves directly as the 

 coding element for translating the associated equipment number. This is 



