REMOTE CONTROLLED LINE CONCENTRATOR 293 



of development of a remote line concentrator for quantity production. 

 The cost of remote line concentrator equipment will determine the ul- 

 timate demand. In the meantime, an effort is being made to take advan- 

 tage of the field trial experiences to reduce costs commensurate with 

 insuring reliable service. 



The author wishes to express his appreciation to his many colleagues 

 at Bell Telephone Laboratories whose patience and hard work have 

 been responsible for this new adventure in exploratory switching de- 

 velopment. An article on line concentrators would not be complete 

 without mention of C. E. Brooks who has encouraged this development 

 and under whose direction the engineering studies were made. 



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