VACUUM TUBE ELECTRONICS 



75 



are the same as those obtained for the diode and are plotted in Figs. 1 

 and 3. Values of the ampHfication factor 



0" = ^ + iu 



are shown in Figs. 5 and 6. 



Fig. 6— Phase angle of amplification factor of negative 

 grid triodes versus transit angle. 



It is evident that radical changes in the phase angles existing be- 

 tween the grid voltage and plate current are present when the transit 

 time becomes appreciable in comparison with the period of the applied 

 electromotive force. The plate impedance decreases in magnitude as 

 also does the magnitude of the amplification factor. However, the 

 ratio of the two, namely, a/z, maintains a fairly constant magnitude 

 as shown in Fig. 7, whose phase angle nevertheless rotates continually 

 m a negative direction becoming equal to 3 radians when t is 27r. 



The interelectrode capacity between cathode and plate is included 

 m the fundamental relations here employed. This inclusion exhibits 

 one important difference between (32) and the classical case. At low 

 frequencies, the equivalent circuit represented by (32) degenerates into 

 that shown on Fig. 8. The capacity branch exists in parallel with the 



