M-O Valve type NR7 valve
date: label: date made
content: ca 1918
name: label: maker
content: Marconi-Osram Valve Co., Ltd.
notes: label: Description (Brief)
content: A double-ended tube with pointed contacts at either end. One contact is set in a rubber base that has two screw-in contacts: "G" and "A". Glass envelope with an external copper strap from one contact to the base. Assembly is mounted perpendicular to the axis of the tube and appears similar to a type R valve. Stamped on envelope: "[?????] by / The M. O. Valve Co. Ltd / QEC / Made in England / [anchor logo]" and "Patt [??]27 / [??] NR7 / 22367". Donor's notes report: "Triode made in England, with cylindrical structure having axis at right angles to the axis of the tube, similar to that of the Morehead Tube used in the U.S., circa 1920." [From list of material compiled by E.S.Purington, Feb. 28, 1966.] Reference: https://www.radiomuseum.org/tubes/tube_nr7.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 the Estate of John H. Hammond, Jr., thru The National Shawmut Bank of Boston
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.327508
label: catalog number
content: 327508
label: accession number
content: 266066
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 1/4 in x 1 1/4 in; 8.255 cm x 3.175 cm