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 126
ed with two master switches, one for each 25 lineswitches. Inthis case 25 lines with their master switch constitute a section. At the very top of the frame is a small powerboard, with bus barsfor the battery, and fuses to protect the apparatus and wiring. Just below the power panel is the terminal… … Fig. 89.—One-hundred-line switchboard, rotary lineswitches (front open). On the back of the frame (Fig. 87) are the connectors which carrytraffic into the 100-line group. Four shelves are provided, so that anynumber of connectors may be installed up to 24. Whenever a connectoris removed, its bank…
Telephone
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