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 sounder was made according to US Patent #678,395, issued 16 July 1901 to John J. Ghegan of Newark, NJ, and was assigned to Bunnell Company for whom Ghegan worked. The idea was to make adjusting the lever arm easier and more precise by the addition of a spring-loaded tuning mechanism. Part of the adjuster can be seen mounted on the base behind the arched yoke.
Currently not on view
date made
ca 1905
J. H. Bunnell & Co.
Physical Description
wood (overall material)
brass (overall material)
rubber (overall material)
overall: 4 in x 3 in x 5 1/2 in; 10.16 cm x 7.62 cm x 13.97 cm
ID Number
model 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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