Western Union type 1-A varistor display model
date: label: date made
content: ca 1941
name: label: Maker
content: Western Union Corporation
notes: label: Description (Brief)
content: A model of a type 1-A varistor made for display purposes. Unit consists of a wooden base on which is mounted a tube socket. The varistor is set in the socket and has an 8-pin plastic base with center post, and a removable T-shaped metal shell. Nameplate reads: "W.U.Tel. Co. / Varistor SPL. / Mfd. by Transmission Lab." A company tag written by F. B. Bramhall notes: "Lucite substituted for bakelite so the copper oxide discs can be seen. This varistor was introduced for multichannel carrier system modulators in 1942. Copper oxide varistors were used for the purpose until 1946 when they were replaced by germanium crystal diodes. .... The Varistor [was] employed in all carrier systems using frequencies above 3150 cycles. Four gold contacted copper oxide rectifier discs connected [as indicated on an attached diagram of the circuit]."
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Western Union Corporation
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.331476
label: accession number
content: 294351
label: accession number
content: 294351
label: catalog number
content: 331476
objectType: label: Object Name
content: Varistor
physicalDescription: label: Physical Description
content: wood (part: material)
label: Physical Description
content: metal (part: material)
label: Measurements
content: varistor: 2 3/8 in x 1 1/8 in; 6.0325 cm x 2.8575 cm
label: Measurements
content: overall: 3 in x 2 3/4 in x 3 in; 7.62 cm x 6.985 cm x 7.62 cm