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. The Bell System technical journal . Fig. 19—Originating marker frame. J CROSSBAR DLAL TELEPHONE SWITCHING SYSTEM 117. Fig. 20—Battery supply feeders, power wiring, fusing, etc. accommodate five senders which may be of one type, or a combinationof both types. The crossbar switch shown on the right of each sub-scriber sender unit, is a part of the sender circuit and is employed forthe purpose of registering the called numbers dialed by the subscribers. 118 BELL SYSTEM TECHNICAL JOURNAL The A operator senders are associated with the A operatorswitchboard equipment and are used for the completio
. The Bell System technical journal . Fig. 19—Originating marker frame. J CROSSBAR DLAL TELEPHONE SWITCHING SYSTEM 117. Fig. 20—Battery supply feeders, power wiring, fusing, etc. accommodate five senders which may be of one type, or a combinationof both types. The crossbar switch shown on the right of each sub-scriber sender unit, is a part of the sender circuit and is employed forthe purpose of registering the called numbers dialed by the subscribers. 118 BELL SYSTEM TECHNICAL JOURNAL The A operator senders are associated with the A operatorswitchboard equipment and are used for the completion of certainclasses of calls such as toll and assistance calls. A view of the originating marker frame is shown in Fig. 19. Therewill be a variation in the equipment on this frame for different citiesdue to the variation in the number of route relays required, the numberdepending upon the number of central office codes that may be dialedby subscribers and operators. This variable feature is cared for byproviding the route relay equipment in bays of 100 codes as shown inthe right-hand bay. The terminal fields sho
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1