National Radio Tube type R3 "Rectobulb"
date: label: date made
content: ca 1932
name: label: maker
content: National Radio Tube Company
notes: label: Description (Brief)
content: National Radio Tube Rectobulb A half-wave mercury-vapor rectifier used as a power supply in radio transmitters. Marked: "National 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 metal cylinder anode (not mesh). Made by National Radio Tube Company, San Francisco. Company formed in 1929. Reference: Tyne, "Saga of the Vacuum Tube," page 359; 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.320894
label: catalog number
content: 320894
label: accession number
content: 241556
objectType: label: Object Name
content: Electron Tube
label: Object Name
content: rectifier
label: Other Terms
content: Electron Tube; Electron Tubes
physicalDescription: label: Measurements
content: overall: 8 1/4 in x 3 in; 20.955 cm x 7.62 cm