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 107
open main fromnegative battery to ground to busy the trunks while hunting for an idletrunk. The skeleton of the circuits arriving from the left through the selectorshows the selector in the act of seizing the trunk. The ground on therelease trunk has not yet been removed. Here we begin. The ground… … ——lk6^>v J ^c. PW \ rTTTii Cham Re/at/
Telephone
Internet Archive · California Digital Library · Public Domain Mark 1.0. Free to use for anything.
