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 628
tate about an axis so thatby turning the knob on topany desired amount of themovable plates can be in-cluded between the fixedplates. Finally, the receiving telephones used in wireless tele-graphy must be doubles-head telephones (Fig. 416) with a Mo table ][.. 11. — Variable receiving condenser.… … Fig. 41G. — Double-headtelephone receivers. resistance of from 1000 to 2500 ohms. Besides these importantinstruments one usually finds in a modern installation numer-ous switches, rheostats, and meters tomeasure current, voltage, and wavelength. 379. The service of radiotelegraphy.The ocean seems…
Electricity · Magnetism
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