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BELL SYSTEM TECHNICAL JOURNAL 



The adaptation of the multiplex to cable operation does not involve 

 any modifications which affect the design of the perforators, trans- 

 mitters, or printers, so that it is possible to employ in this system the 

 same type of instruments used in land line operation. 



In cases where it is desirable to link two cable sections together 

 automatic repetition is provided for by the provision of additional 

 sending and receiving commutators on the repeater distributor for 

 transmitting and receiving on the second section. A photograph of 

 such a repeater distributor is shown in Fig. 8. The incoming signals 



Fig. 8 



at the repeater are received in the regular way and operate the vibrating 

 relay which applies the completely corrected impulses to the receiving 

 segments. The receiving segments, instead of being connected to the 

 selector magnets of a printer, are connected to the windings of storing 

 relays which are operated by the incoming signal combinations and 

 set up the identical combinations on the corresponding sending 

 segments associated with the next section of cable. The storing 

 relays thus perform the same function as a tape transmitter except 

 that they are controlled directly by the received signals instead of a 

 perforated tape. With this method ^^ of repetition it is possible to 

 replace the storing relays on any channel with a printer and trans- 

 "»E. P. Bancroft, et al., U. S. Patent No. 1,541,316. 



