Telegraph Test Unit
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. This small, pocket-sized unit was both transmitter and receiver. It has a leather case and was used by Western Union personnel in the field for testing telegraph lines.
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
label: See more items in
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.332065
label: accession number
content: 294351
label: catalog number
content: 332065
label: collector/donor number
content: 100-050
objectType: label: Object Name
content: pocket telegraph
label: Object Name
content: telegraph test unit
label: Object Name
content: telegraph set
physicalDescription: label: Physical Description
content: leather (overall material)
label: Physical Description
content: metal (overall material)
label: Physical Description
content: plastic (overall material)
label: Measurements
content: overall: 2 3/8 in x 5 3/4 in x 2 7/8 in; 6.0325 cm x 14.605 cm x 7.3025 cm