GE / RCA type UX222 screen grid tetrode
date: label: date made
content: 1927
name: label: maker
content: General Electric Company
notes: label: Description (Brief)
content: A plastic 4-pin base with top contact, S-shaped envelope. Donor's card reads: "Screen grid tube made by General Electric for the Radio Corporation of America in October 1927. The first screen grid tube made available in production quantities. A predecessor of the UX-224, the first screen grid tube for use in AC radio receivers. These tubes sold in 1934 for $1.50 each. Filament: 3.3 volts at .132 ampere. For use in parallel with the UX-199 tube filaments, or on a 6 volt battery circuit through a special resistor made by the Amperite Company, 135 volts on the plate, 45 to 67 volts on the screen, and a 1.5 volt negative control grid bias. Since tubes with top caps were new to the field and it would also fit a standard UX socket, much confusion resulted from the fact that the control grid was connected to the top cap and the screen to the "grid" connection on the socket. Thoriated tungsten filament." See also:https://www.radiomuseum.org/tubes/tube_ux222.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 Paul G. Watson
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.324407
label: catalog number
content: 324407
label: accession number
content: 252994
objectType: label: Object Name
content: Electron Tube
label: Object Name
content: tetrode
label: Other Terms
content: Electron Tube; Electron Tubes
physicalDescription: label: Measurements
content: overall: 5 in x 1 3/4 in; 12.7 cm x 4.445 cm