Abstract
This apparatus is designed to measure the polarity and the strength of the electric field in the thunderclouds. It utilizes, like Simpson and Scrase's apparatus, the point discharge current in the antenna, but the method of utilization is entirely different from their method. In our apparatus the condenser is charged by the point discharge current, and it is discharged through neon tubes. By counting the number of discharges we can know the strength of the field. To find out the sign of the electric field, we make use of one of the properties of the neon tube, that is, the polarity of the neon tube. For this purpose, neon tubes having considerable polarity (about 20-40V) is specially made. Finally the measuring circuit is introduced in the grid circuit of short wave oscillator which emits waves of about 15 MC, so that by receiving the wave we can measure the field of the thunderclouds immediately at the ground station. The weight of this oscillator is about 60g with battery, and when fully equipped with antenna, parachute, etc., it becomes about 900g.
