An elementary book on electricity and magnetism and their applications (1919)
Jackson, Dugald C. (Dugald Caleb), 1865-1951, Jackson, John Price, b. 1868, Black, Newton Henry, b. 1874 · New York, The Macmillian Co · leaf 596
Fig. 385. — Simple form of switchboardfor small exchanges. THE TELEPHONE 531 SUBSCRIBERS … ft here only in the briefest outline. The principle upon whichit is based is to divide the total number of subscribers linesinto sets, each of which is brought to a different section of theswitchboard where the lines belonging to one particular setmay be looked after by one operator. The lines are…
Electricity · Magnetism
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