Freshman variable resistance grid leak
date: label: date made
content: 1922
name: label: maker
content: Charles Freshman Co.
notes: label: Description (Brief)
content: Marked: Box: "Resistance: Zero to 5 megohms / Capacity: .0005 M.F. / Sole Manufacturers / Chas. Freshman Co., Inc. New York City". A variable resistance grid leak detector in original box. The grid leak evolved as a method of utilizing a triode vacuum tube as a detector and amplifier. Specimen is a fixed capacitor shunted with a variable resistance which can be varied from 0-5 megohms. Binding posts connect to external circuit. See US Patent 1,599,225, Variable Grid Leak, issued to Albert Franklin, October 5, 1922.
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.321706
label: accession number
content: 241556
label: catalog number
content: 321706
objectType: label: Object Name
content: grid leak
physicalDescription: label: Measurements
content: unit: 1 in x 2 1/2 in x 1 in; 2.54 cm x 6.35 cm x 2.54 cm
label: Measurements
content: box: 1 1/8 in x 2 1/2 in x 1 1/4 in; 2.8575 cm x 6.35 cm x 3.175 cm