Dumont 3" type 1 "Phasmajector" cathode ray tube - "Dumont Television"
name: label: maker
content: DuMont Company
notes: label: Description (Brief)
content: Inked on stem press: "9578", printed on target "Dumont Television". Marked on glass: Dumont (/) Phasmajector type-1 (/) Made in U.S.A." A 7-pin plastic base with top and side contacts, gold ring around the tube connects to side contact. Vertical and horizontal deflection plates, envelope rounded on end.
label: Description (Brief)
content: By the late 1930s live-action camera tubes were available from both RCA and Farnsworth. However for scientific checks of system performance fixed-image tubes called phasmajectors (from the Greek for image emitter) were used by television stations and by experimenters needing reliable test signals. A metal target plate within the tube was imprinted with a desired picture or test pattern. An electron beam sweeping across the target would strike with enough velocity to release secondary electrons whose density varied according to the target pattern.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Fairchild Camera and Instrument Corporation, Dumont Laboratories Div., thru Edgar S. Hill
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.328283
label: catalog number
content: 328283
label: accession number
content: 270517
objectType: label: Object Name
content: Electron Tube
label: Object Name
content: cathode ray tube
physicalDescription: label: Measurements
content: overall: 12 in x 3 1/2 in x 3 in; 30.48 cm x 8.89 cm x 7.62 cm