Crossed-field amplifier theory of operation.
<a href="//commons.wikimedia.org/wiki/User:%D0%94.%D0%98%D0%BB%D1%8C%D0%B8%D0%BD" title="User:Д.Ильин">Д.Ильин</a>: vectorization
<a href="//commons.wikimedia.org/wiki/File:Crossed_field_amplifier.png" title="File:Crossed field amplifier.png">File:Crossed field amplifier.png</a> by <a href="//commons.wikimedia.org/wiki/User:Nanoatzin" title="User:Nanoatzin">Nanoatzin</a>