Flame-proof Telegraph Key
date: label: date made
content: ca 1918
name: label: maker
content: Marconi Wireless Telegraph Co. of America
notes: label: Description (Brief)
content: Telegraph keys are electrical on-off switches used to send messages in Morse code and can spark when the circuit opens. Flame-proof telegraph keys, like this one made by American Marconi, 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: Label reads: "Flame Proof Hand Key - 1/2 K.W. / Volts 300 Amperes 5 Cycles 500 / Type SE86 Serial No. 235 / Mf'd by Marconi Wireless Telegraph Co of America." This unit is a 500 watt flame-proof hand key designed for submarine transmitters. A U-shaped lever arm operates internal contact points. A double-grip knob is affixed to arm. Spring action is adjustable. Marble-type base with two binding posts. Reference: Navy Type Numbers, 1918.
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
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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.320852
label: catalog number
content: 320852
label: accession number
content: 241556
objectType: label: Object Name
content: sending key
label: Object Name
content: telegraph key
label: Other Terms
content: telegraph key; Radio
physicalDescription: label: Physical Description
content: metal (overall material)
label: Physical Description
content: wood (overall material)
label: Physical Description
content: plastic (overall material)
label: Measurements
content: overall: 3 3/8 in x 2 3/4 in x 9 in; 8.5725 cm x 6.985 cm x 22.86 cm