Flame-proof Telegraph Key
date: label: date made
content: 1918
label: associated date
content: 1918
name: label: maker
content: Connecticut Telephone & Electric Company
notes: label: Description (Brief)
content: Telegraph keys are electrical on-off switches used to send messages in Morse code. They can spark when the circuit opens. Flame-proof telegraph keys, like this one made by Connecticut Telephone & Electric, were designed to contain the spark within a sealed chamber. These keys were necessary on early aircraft and in confined spaces such as aboard ships and submarines where the spark might ignite flammable gasses.
label: Description (Brief)
content: Molded on cover: "Signal Corps U.S. Army / Flame Proof Key / Type J. 5. / Date Mar.18.1918. Order 41973 / Connecticut Tele & Elec. Co." A small World War I type wireless key with knob and grip. The flange is to protect the operator from electrical shocks caused by the high current draw of early wireless transmitters. Unit includes an adjusting tension screw and single lever action.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
label: See more items in
content: Telegraph Keys
label: See more items in
content: Communications
creditLine: label: Credit Line
content: from Franklin Wingard
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.321623
label: catalog number
content: 321623
label: accession number
content: 241556
objectType: label: Object Name
content: telegraph key
label: Other Terms
content: telegraph key; Radio
physicalDescription: label: Physical Description
content: brass (overall material)
label: Physical Description
content: copper (overall material)
label: Physical Description
content: steel (overall material)
label: Physical Description
content: bakelite (overall material)
label: Measurements
content: overall: 2 1/2 in x 2 7/8 in x 4 3/4 in; 6.35 cm x 7.3025 cm x 12.065 cm