Telegraph Sounder and Speaking Telephone

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. Inventor Amos Dolbear, known for his early experiments in telephony, made this patent model of a combination device that worked both as a telegraph sounder and a telephone receiver.

Date Made: 1879

Maker: Dolbear, Amos E.

Location: Currently not on view

See more items in: Work and Industry: Electricity, Communications, Telegraph Sounders


Exhibition Location:

Data Source: National Museum of American History

Id Number: EM.252631Catalog Number: 252631Accession Number: 49064Patent Number: 220205

Object Name: patent modeltelegraph receivertelephonetelegraph sounderObject Type: Patent ModelOther Terms: telegraph sounder; Telephones

Physical Description: wood (overall material)metal (overall material)rubber (overall material)cloth (overall material)Measurements: overall: 4 1/4 in x 4 1/2 in x 4 1/4 in; 10.795 cm x 11.43 cm x 10.795 cm


Record Id: nmah_703436

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