Telegraph Sounder
date: label: date made
content: ca 1869
notes: label: Description (Brief)
content: Telegraph sounders convert electrical pulses into audible sounds and are used to receive Morse code messages. The message travels as a series of electrical pulses through a wire. Short pulses make a dot, slightly longer pulses make a dash. The sequence of dots and dashes represent letters and numbers. The pulses energize the sounder’s electromagnets which move a lever-arm. The arm makes a loud “click” when it strikes a crossbar and the operator translates the pattern of sounds into the original language.
label: Description (Brief)
content: This sounder was made using US Patent #92284, issued July 6, 1869 to William Davis of Jersey City, NJ. Davis' idea was to make the sounder produce a "clear tone" by using a hollow resonating chamber made of hard rubber. The chamber can be seen mounted on the base next to the electromagnet. The anvil with its adjusting screws is mounted on top of the chamber. When the lever strikes the anvil the resonating chamber amplifies the sound.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
label: See more items in
content: Communications
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content: Telegraph Sounders
creditLine: label: Credit Line
content: from Western Union Corporation
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.331979
label: accession number
content: 294351
label: catalog number
content: 331979
label: collector/donor number
content: 100-038
objectType: label: Object Name
content: telegraph receiver
label: Object Name
content: telegraph sounder
label: Other Terms
content: telegraph sounder; Telegraphy
physicalDescription: label: Physical Description
content: wood (overall material)
label: Physical Description
content: brass (overall material)
label: Physical Description
content: rubber (overall material)
label: Measurements
content: overall: 3 3/4 in x 5 1/4 in; 9.525 cm x 13.335 cm