McCandless / De Forest spherical "Audion" radio tube
date: label: date made
content: 1912
label: associated date
content: 1910
name: label: associated person
content: De Forest, Lee
label: maker
content: De Forest Radio Telephone & Telegraph Co.
label: maker
content: H. W. McCandless & Company
notes: label: Description (Brief)
content: Donor card: "Spherical double audion, two plates and two grids, made about 1912 by H. W. McCandless for Lee De Forest. 3.5 volt tungsten filament, wrapped with tantalum for increased emission. Referred to in De Forest letter of 22 April 1954 as #5." Brass candelabra screw base with glass insulator, two filaments.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Paul G. Watson
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.324300
label: catalog number
content: 324300
label: accession number
content: 252994
objectType: label: Object Name
content: Electron Tube, Triode
label: Object Name
content: triode
label: Other Terms
content: Electron Tube, Triode; Electron Tubes
physicalDescription: label: Measurements
content: overall: 3 1/2 in x 2 in; 8.89 cm x 5.08 cm