. Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems . IC TELEPHONES 315 Consider the case of two adjacent exchanges which have free servicefrom one to the other. (Fig. 268.) Let each exchange be representedby four 100-line boards, having selectors and connectors. The lines, 1 and 2, which carry the inter-exchange traffic, are equippedat each end with a selector, and are in addition multipled to the banksof local selectors. A repeater is inserted between the selector banks andthe lines for the purpose of holding the local switches from releasing,feeding commo
. Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems . IC TELEPHONES 315 Consider the case of two adjacent exchanges which have free servicefrom one to the other. (Fig. 268.) Let each exchange be representedby four 100-line boards, having selectors and connectors. The lines, 1 and 2, which carry the inter-exchange traffic, are equippedat each end with a selector, and are in addition multipled to the banksof local selectors. A repeater is inserted between the selector banks andthe lines for the purpose of holding the local switches from releasing,feeding common battery for talking, etc. The banks of the toll selectors are connected to the jacks of tollconnectors, one or more in each 100-line board. These toll connectorshave their banks multipled to the banks of the local connectors, so thatall subscriber lines can be reached. When a subscriber in exchange A desires to call one in B, he dials afigure which causes his first selector to seize one of the lines, making itbusy on the banks of all the other first selectors in both exchanges A and. Fig. 269.—Radial system of exchanges. B. He then dials the call number of the desired telephone, which operatesthe toll selector at B and the toll connector in the 100-line board chosen. Radial or Satellite Exchange System.—The radial or satellite systemof exchanges consists of a central exchange connected by radial trunksor toll lines to outlying smaller automatic exchanges. ( 269.) Thecentral exchange (manual or automatic) is the controller of the each community automatic exchange completes its own con-nections, it depends on the controlling exchange for all connections to thecenter or to other exchanges. Many small exchanges are still operated manually, because it isnecessary to keep someone there tomake toll connections, and that sameperson can answer local calls in addition to the light toll business. Cen-tralized toll switching removes this necessity and permits the
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttelephone, bookyear19
