This primary source comes from the Records of the Patent and Trademark Office.
National Archives Identifier:
6277803Full Citation: Patent Drawing for G. Marconi's Apparatus for Wireless Telegraphy; 6/28/1904; Records of the Patent and Trademark Office, Record Group 241. [Online Version, https://www.docsteach.org/documents/document/patent-drawing-for-g-marconis-apparatus-for-wireless-telegraphy, May 6, 2024]