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
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
Credit Line
from Western Union Corporation
See more items in
Work and Industry: Electricity
Telegraph Sounders
Data Source
National Museum of American History


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