. The Bell System technical journal . _Ca_ll_Cireuit_A BOARD B BOARD Fig. -1—Diagram Showing Manual Interoffice Connection Such communication between the two operators as is necessary toestablish this connection takes place over a special pair of wires knownas a call circuit. 58 BELL SYSTEM TECHNICAL JOURNAL The method, ol which the above is a bare outline, is that used incompleting ordinary connections. Different arrangements and differ-ent operating methods have to be provided for handling short haultoll calls, long distance calls, calls from coin boxes, and calls of manyother kinds. In the
. The Bell System technical journal . _Ca_ll_Cireuit_A BOARD B BOARD Fig. -1—Diagram Showing Manual Interoffice Connection Such communication between the two operators as is necessary toestablish this connection takes place over a special pair of wires knownas a call circuit. 58 BELL SYSTEM TECHNICAL JOURNAL The method, ol which the above is a bare outline, is that used incompleting ordinary connections. Different arrangements and differ-ent operating methods have to be provided for handling short haultoll calls, long distance calls, calls from coin boxes, and calls of manyother kinds. In the simplest types of manual systems, the subscriber, in orderto signal the central office, turns a crank thus operating a magnetogenerator. This throws a drop in front of an operator at the centraloffice. In the switchboards developed to meet the needs of the largerareas, electric lamps are substituted for the drop, and relays auto-matically controlled by the subscriber bring them into play at theproper time. Electric lamps which serv
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
