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 116
others will serve as well, and must be tested, selected, andused. The group connector is arranged to perform the above duties. Itmay operate with the customary two digits, being called a 2-digit groupconnector or rotary connector, to distinguish it from the ordinaryline connector which connects…
Telephone
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