408 



THE BELL SYSTEM TECHNICAL JOURNAL, APRIL 1951 



Suppose one grid is at a large negative potential, cutting off that tube, and 

 the other is at a positive potential or at zero potential. The potential of the 



R2 



Fig. 16— Two-stage transistor amplifier using a single power supply. 



Fig. 17 — Multivibrator and duals. 



negative grid rises toward zero at a rate controlled by the grid resistor and 

 the coupling condenser. When the grid potential rises above the cutoff 



