Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems (1921)
Smith, Arthur Bessey, b. 1875, Campbell, Wilson Lee · New York : McGraw-Hill · leaf 75
ers, and furnishespositive battery to the back-bridge relay BBR. 58 A UTOMA Tl( • TELEPHON V When the lineswitch connects a calling subscriber line to a connector,the line relay of the connector immediately pulls up and energizes therelease relay. The latter grounds the release trunk so that the… … Line Bank Fig. 59.—Switch mechanism. When the subscriber dials the first digit of the call number, the line-relay armature vibrates one complete cycle for each unit in the digit.Thus it feeds current alternately to the release relay and to the verticalmagnet. The former is slow release, and remains…
Telephone
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