<b>Toroidal transformer</b> used to control the voltage (0-100 kV) of an x-ray bulb in a x-ray diffraction system for the analysis of minerals
<a href="//commons.wikimedia.org/wiki/User:Hgrobe" title="User:Hgrobe">Hannes Grobe</a>/AWI
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>