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 is the only example of a sounder in the collection made by Hardwick-Hindle Company, an electrical manufacturer founded by John C. Hindle Sr. and Ambie Hardwick in 1924.
Currently not on view
Object Name
telegraph receiver
telegraph sounder
date made
ca 1928
Hardwick-Hindle Company
Physical Description
wood (overall material)
brass (overall material)
rubber (overall material)
overall: 5 in x 4 in x 6 1/2 in; 12.7 cm x 10.16 cm x 16.51 cm
ID Number
accession number
catalog number
See more items in
Work and Industry: Electricity
Telegraph Sounders
Data Source
National Museum of American History, Kenneth E. Behring Center


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