<a href="https://en.wikipedia.org/wiki/Klystron_tube" class="extiw" title="w:Klystron tube">w:Klystron tube</a> found at the <a href="https://en.wikipedia.org/wiki/Canberra_Deep_Space_Communications_Complex" class="extiw" title="w:Canberra Deep Space Communications Complex">w:Canberra Deep Space Communications Complex</a>.  This is a high power microwave oscillator tube.  I took this photo on a university trip.
<a href="https://en.wikipedia.org/wiki/User:Enochlau" class="extiw" title="en:User:Enochlau">Enoch Lau</a>. As a courtesy, please let me know if you alter this image or this image description page.
CC BY-SA 3.0
Photo taken by uploader