THE CATHODE RAY OSCILLOGRAPH 19 



age reaches this value the tube operates to discharge the condenser 

 suddenly, and then the uniform charging process begins over again. 

 The condenser voltage applied to one pair of plates of the oscillograph 



Fig. 23 — Discharge of condenser through inductance. 



tube makes the spot travel over the screen at a uniform rate in one 

 direction, returning much faster in the other direction. This process 

 may be repeated once a second, or many thousand times a second, 

 depending on the frequency of the wave that is being studied. 



Fig. 24 — Discharge of condenser through chattering contact. 



In Figs. 23-29 are shown a number of records plotted on a time 

 basis. Figs. 23-25 were made with the Western Electric tube, Figs. 

 26-27 with the Dufour oscillograph, and Figs. 28-29 on an oscillograph 

 of the type of Rogowski. 



