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 169
n Orange4\Q J(D 2§ lty\ Thread ~\ To Line Call Device Fig. 147.—Desk telephone wiring diagram. .-£*_ … £>_ rQCni Ringer ^ Shunt•^Imp. Cal/.Device r 3Cond. Cord. ^P , Red I C—i! 02 W Orange Call Device Fig. 148.—Wiring diagram for a wall telephone with an extension.
Telephone
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