U.S. Army Signal Corps / Ballantine model BC-216 microphone amplifier
date: label: date made
content: ca 1939
name: label: maker
content: Ballantine Laboratories, Inc.
notes: label: Description (Brief)
content: Markings: "Signal Corps / US Army / Microphone Amplifier / BC 216-A / Serial No. C. / Made by / Ballantine Labs., Inc. / Boonton, New Jersey".
label: Description (Brief)
content: Amplifier designed for use with T-20 throat microphone. Designed and developed for the US Army Air Force by Stuart Ballantine of Ballantine Labs., Inc. Boonton, NJ. Known as "talking collars" throat microphones permitted aviators to communicate without removing hands from aircraft controls. According to the donor, this amplifier, "produced an output which was reasonably uniform over the voice range even though the energy picked up at the throat level was far from uniform." References: US Patents 2121778 through 2121781, and 2122191, issued 28 June 1938 to Stuart Ballantine. According to a newspaper account, the Army had been secretly testing Ballentine's throat microphones for "more than three years" at the time the patents issued. Stephen McDonough, "Talking Collar," NY Journal and American, 17 July 1938.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Ballantine Laboratories, Inc. thru A. W. Parkes
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.325634
label: catalog number
content: 325634
label: accession number
content: 256739
label: serial number
content: C
objectType: label: Object Name
content: Amplifier, Microphone
label: Object Name
content: microphone component
label: Other Terms
content: Amplifier, Microphone; Radio
physicalDescription: label: Measurements
content: overall: 7 in x 8 1/2 in x 3 in; 17.78 cm x 21.59 cm x 7.62 cm