Armstrong oscillator (English Wikipedia)

Analysis of information sources in references of the Wikipedia article "Armstrong oscillator" in English language version.

refsWebsite

Global rank English rank

800^th place

676^th place

1hathitrust.org

441^st place

311^th place

espacenet.com (Global: 800^th place; English: 676^th place)

worldwide.espacenet.com

US 1113149, Armstrong, Edwin H., "Wireless receiving system", published 19 October 1913, issued 6 October 1914 . In Figure 1, a tapped inductor ("auto-transformer") provides the feedback; in Figure 6, a transformer provides the feedback.
DE 291604, Meissner, Alexander, "Einrichtung zur Erzeugung elektrischer Schwingungen", published April 10, 1913, issued June 23, 1919

hathitrust.org (Global: 441^st place; English: 311^th place)

babel.hathitrust.org

Edwin H. Armstrong, Some recent developments in the audion receiver, Proceedings of the Institute of Radio Engineers, September 1915, pages 215-238