Tuning helix for radio
date: label: date made
content: 1912
notes: label: Description (Brief)
content: No markings. Homemade oscillation transformer used by John B. Brady in early amateur wireless transmitter. One coil is 11" in diameter and consists of 5 turns of 1/2" wide copper stripping. The second coil is 12" in diameter., and consists of 11 turns of 3/8" copper stripping. Two slide rods permit adjustable coupling and paper clips are employed for tapping purposes.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from John B. Brady, thru Mrs. John B. Brady
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.321937
label: accession number
content: 245709
label: catalog number
content: 321937
objectType: label: Object Name
content: Electron Tube, Triode
label: Object Name
content: triode
label: Object Name
content: coil
label: Other Terms
content: Electron Tube, Triode; Electron Tubes; Radio
physicalDescription: label: Measurements
content: overall: 15 in x 14 in x 7 1/2 in; 38.1 cm x 35.56 cm x 19.05 cm