We found this circuit in an old publication on tube oscilloscopes. The circuit allows to visualize the family of curves of a pentode for several tensions applied to the grid. The wire potentiometer can be 47 k ohms.
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We found this circuit in an old publication on tube oscilloscopes. The circuit allows to visualize the family of curves of a pentode for several tensions applied to the grid. The wire potentiometer can be 47 k ohms.