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 by the L. S. Brach Co., Newark, N.J., around the time of the First World War. The only Brach sounder in the collection, this unit has the electromagnets mounted horizontally instead of the more common vertical orientation. We do not know if this was simply a design feature or if the company believed the sounder worked better with the electromagnets in that configuration.
Currently not on view
date made
ca 1915
L. S. Brach Manufacturing Co.
Physical Description
wood (overall material)
brass (overall material)
rubber (overall material)
overall: 3 5/8 in x 2 3/4 in x 5 3/8 in; 9.2075 cm x 6.985 cm x 13.6525 cm
ID Number
collector/donor 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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