Electrical measuring instruments : grand prize Louisiana Purchase Exposition, St. Louis, 1904 (1904)
Leeds and Northrup Company · leaf 37
ccording as the current has decreased or increased. The contactP is immediately moved in the same direction, until the spot of light isbrought back to zero, when the circuit is again closed, a point is printed,the spot of light again goes off the zero, and so on. Tw^enty points aminute can be… … Fig. 6 The contact maker shown in Fig. 6 is directly connected to the gen-erator or may be driven by a synchronous motor. In the latter case thecurves would not be quite accurate if any departure from strict synchro-nism occurred. A disc of hard rubber mounted on the shaft revolves atthe same…
