Telegraph Sounder

Description (Brief):

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 self-contained, so-called "secret sounder" was used by Western Union's Switching Development Division as a field test unit.

User: Western Union Corporation

Location: Currently not on view

See more items in: Work and Industry: Electricity, Communications, Telegraph Sounders


Exhibition Location:

Credit Line: from Western Union Corporation

Data Source: National Museum of American History

Id Number: EM.331949Serial Number: 19Collector/Donor Number: 100-891Accession Number: 294351Catalog Number: 331949

Object Name: telegraph receivertelegraph sounder

Physical Description: wood (overall material)brass (overall material)rubber (overall material)paper (overall material)Measurements: overall: 4 1/4 in x 8 1/4 in x 9 3/8 in; 10.795 cm x 20.955 cm x 23.8125 cm


Record Id: nmah_891107

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