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THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1953 



storage section of the gate. The connector block number is ascertained 

 from the peg identification or from the call slip. If the connector is free 

 a CONN READY (r) lamp lights to indicate that the peg and slip should be 

 advanced to the connector block in the active section of the gate. If the 

 connector is not ready, the lamp will light at some subsequent time 

 and the connector delay time will be noted on the call slip. If several 

 calls pile up in a particular storage connector block, means are provided 

 for maintaining correct preference for entry into the active section in 

 the case of registers. With line originations, a random line preference 

 circuit under key control at the right side of the originating position 

 key shelf picks, on a random basis, the next entry into the active section 

 of the gate (except in the case of preferred lines whose pegs will have a 

 distinctive marking) and which have precedence over ordinary lines. Keys 

 for a choice of one out of two, three, four or five are provided. With 



INCOMING TRUNK AND REGISTER 

 WAITING FOR MARKER 



ORIGINATING REGISTER 

 WAITING FOR MARKER 



LINE LINK FRAME MARKER CONNECTOI 

 ORIGINATING REGISTER MARKER CONNECTORS- 

 INCOMING REGISTER v-^^-R CONNECTORS—, 



MARKER 



PREFERENCE 



KEY 



ACTIVE SECTION 



INCOMING TRUNKS 



AND REGISTERS 



WAITING FOR CONNECTOR 



STORAGE SECTION 



SUBSCRIBER 

 WAITING FOR CO 



Fig. 18 — The gate for control of marker connector preference. 



