National Radio Tube type R-3 "Rectobulb"
date: label: date made
content: ca 1930
name: label: maker
content: National Radio Tube Company
notes: label: Description (Brief)
content: National Radio Tube type R-3 Rectobulb. Marked: "National Radio / Tube Co." and "Choke input / to filter / must be used / with all / Rectobulbs." Cathode label missing. Base stamped: "National / R-3 / Rectobulb". A double-ended rectifier tube with a 4-pin base including filament connections on one end, and a plate lead on top. Unit has a mesh cylinder anode. Reference: Tyne, "Saga of the Vacuum Tube," page 359; and https://www.radiomuseum.org/tubes/tube_r3_rectobulb.html.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Franklin Wingard
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.322484
label: catalog number
content: 322484
label: accession number
content: 241556
objectType: label: Object Name
content: Electron Tube
label: Object Name
content: ractifier
label: Object Name
content: rectifier
physicalDescription: label: Measurements
content: overall: 8 1/4 in x 3 in; 20.955 cm x 7.62 cm