==Kilder/referencer==
{{reflist|refs=
<ref name="Gilmour">{{cite book
 | last1  = Gilmour
 | first1 = A. S. 
 | title  = Klystrons, Traveling Wave Tubes, Magnetrons, Crossed-Field Amplifiers, and Gyrotrons 
 | publisher = Artech House
 | date   = 2011
 | pages  = 317–18
 | url    = https://books.google.com/books?id=l_1egQKKWe4C&q=%22traveling+wave+tube&pg=PA317
 | isbn   = 978-1608071852
 }}</ref>
<ref name="Whitaker">{{cite book
 |last1        = Whitaker
 |first1       = Jerry
 |title        = Power Vacuum Tubes Handbook, 3rd Edition
 |publisher    = CRC Press
 |date         = 2016
 |location     = 
 |pages        = 87
 |language     = 
 |url          = https://books.google.com/books?id=06jMBQAAQBAJ&pg=PA87&dq=Tetrode+%22secondary+emission%22+%22other+electrons%22
 |doi          = 
 |id           = 
 |isbn         = 1439850658
 |access-date  = 14. juli 2019
 |archive-date = 15. december 2019
 |archive-url  = https://web.archive.org/web/20191215210529/https://books.google.com/books?id=06jMBQAAQBAJ&pg=PA87&dq=Tetrode+%22secondary+emission%22+%22other+electrons%22
 |url-status   = ok
}}</ref>
}}
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