Editor's Note: The last electroscope I used employed gold leaves or pith balls to indicate charge, but here's an electronic version with no moving parts. Though one of our reviewers felt the design ...

This diy electroscope circuit can precisely measure electrostatic charge. The charge to be measured is stored on C1 (a high quality MKT capacitor with a value of 1-2 μF). The voltage (U) across the ...

I SUPPOSE teachers still use gold-leaf electroscopes for their junior lectures; certainly I have found nothing else so dead-beat, or so readily understood; and by projecting with a lens a shadow of ...