Telegraph Sounder

Telegraph Sounder

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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. The type 1-B sounder was a very common model for main line use. This unit was rated at 400 ohms resistance. This particular sounder is mounted on a display plate from the Western Union Museum and gives a manufacturing date of 1928.
Location
Currently not on view
Object Name
telegraph receiver
telegraph sounder
Other Terms
telegraph sounder; Telegraphy
date made
1928
maker
J. H. Bunnell & Co.
Physical Description
wood (overall material)
brass (overall material)
rubber (overall material)
Measurements
overall: 4 3/4 in x 9 in x 7 in; 12.065 cm x 22.86 cm x 17.78 cm
ID Number
EM.331937
accession number
294351
catalog number
331937
collector/donor number
06-22
Credit Line
from Western Union Corporation
See more items in
Work and Industry: Electricity
Communications
Telegraph Sounders
Data Source
National Museum of American History
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