General Electric / RCA model UT-1367 magnetic modulator
date: label: date made
content: ca 1921
name: label: maker
content: RCA Corporation
label: maker
content: General Electric Company
notes: label: Description (Brief)
content: Marked: "Magnetic Modulator / 3.5 to 5 Amp. Model UT-1367 / Manufactured for / Radio Corporation of America / by General Electric Company, U.S.A." Label sticker: "Pat. Nov. 28, 1916; Mar. 13, 1917; May 22, 1917; Jan. 20, 1920. Licensed only for amateur and experimental use. 12-2-21." This device, designed for amateur radio transmitters, stems from experiments with the Alexanderson Magnetic Amplifier. The basic principle involves the usage of iron properties at radio frequencies in controlling or modulating the output of an oscillating vacuum tube or other undamped wave generator. The device is inserted in the antenna circuit of a transmitter where the resistance is less than 15 ohms. Microphone control current with the unit idle is 500 ma. maximum, and 100-650 mils under actual operation. Two model UT-1367 units connected in parallel can modulate an antenna current of 5 amperes. Reference: RCA 1922 Catalog, "Radio Enters the Home", pages 93-94.
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.321672
label: catalog number
content: 321672
label: accession number
content: 241556
objectType: label: Object Name
content: magnetic modulator
physicalDescription: label: Measurements
content: overall: 3 in x 9 3/4 in x 3 1/2 in; 7.62 cm x 24.765 cm x 8.89 cm