A Device for Showing the Direction of Motion of the Oscilloscope Spot
Erika Mann · Review of Scientific Instruments · 1934
A circuit is described which has for its purpose the determination of the direction of rotation of the fluorescent spot obtained in current-voltage oscillograms. The figure described by the rotating spot is interrupted at a suitable point in the cycle by means of a neon lamp discharge, and examination of this interrupted figure readily leads to the correct conclusion as to the direction of rotation which prevailed in the original figure.