Annual report of the Board of Regents of the Smithsonian Institution . -AAAMA/VAV-J I—=—J. Pig. 18. Fig. 19. Connections for oscillation valve used as radiotelegraphic dclector. tion of the voltage applied to it, and in this second method the valveand receiving circuits are arranged as shown in figure 20. In thiscase, we have to apply to the ionized gas a unidirectional electromotiveforce which corresponds to a point of inflexion on the character-istic curve, and then to add to thisvoltage the alternating voltage of theoscillations set up by the incident elec-tric waves in the receiving circui
Annual report of the Board of Regents of the Smithsonian Institution . -AAAMA/VAV-J I—=—J. Pig. 18. Fig. 19. Connections for oscillation valve used as radiotelegraphic dclector. tion of the voltage applied to it, and in this second method the valveand receiving circuits are arranged as shown in figure 20. In thiscase, we have to apply to the ionized gas a unidirectional electromotiveforce which corresponds to a point of inflexion on the character-istic curve, and then to add to thisvoltage the alternating voltage of theoscillations set up by the incident elec-tric waves in the receiving circuit. Theresult is to cause a change in the aver-age value of the current through thetelephone, and therefore to produce asound in it, long or short, according tothe number of trains of waves fallingon the antenna. This last method,then, requires the application in thetelephone circuit of an accurately ad-justed steady electromotive force, notany electromotive force, but just thatvalue which corresponds to a point on the characteristic curve atwhich there is a sudden change of curvature.
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Keywords: ., bookauthorsmithsonianinstitutio, bookcentury1800, bookdecade1840
