Telegraph Resonator

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. A resonator like this was used to amplify the sound, making it easier for an operator to hear his or her own sounder when working in a room filled with these devices. Units made of paper mache were used in the Western and Southern Divisons of Western Union.
Currently not on view
date made
Physical Description
paper mache (overall material)
metal (overall material)
overall: 10 1/2 in x 9 7/8 in x 5 1/4 in; 26.67 cm x 25.0825 cm x 13.335 cm
ID Number
accession number
collector/donor number
catalog number
Credit Line
from Western Union Corporation
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Work and Industry: Electricity
Telegraph Sounders
Data Source
National Museum of American History