File:Technology klystron tube Raytheon and Tesla 004 (52355749113).jpg - Wikimedia Commons
Type VA-842 klystron | National Museum of American History
What is Klystron? What is Two-cavity Klystron? Construction and Working - Electronics Desk
Klystron - Radartutorial
How a Klystron Tube Works - YouTube
Klystron Tube - Precision Microwave
File:Klystron tube, 425 MHz, Varian Corporation, 1959, used in Thule, Greenland, radar station - National Museum of American History - DSC00012.jpg - Wikimedia Commons