National "Browning-Drake Transformer" barrel coil
date: label: date made
content: ca 1925
name: label: maker
content: National Company
notes: label: Description (Brief)
content: National "Browning-Drake Transformer" barrel coil variable inductance, maker's tag: "National / Browning-Drake / Pat. Transformer Pend. / National Co Inc - Cambridge, Mass." Plastic barrel with copper coil wrapped around the outside. A shorter coil with two thin-wire wraps (green silk insulated) around the outside is mounted in the bottom of the barrel coil. A shaft with plastic knob actuates the smaller coil by rotating it within the larger coil. Seven wire stubs with solder residue are set on the barrel coil indicating that this unit has been used.
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.241556.195
label: accession number
content: 241556
label: catalog number
content: 241556.195
objectType: label: Object Name
content: variable inductance
physicalDescription: label: Measurements
content: overall: 3 in x 4 1/2 in x 8 1/2 in; 7.62 cm x 11.43 cm x 21.59 cm