Repeater for Farmer duplex telegraph
date: label: date made
content: ca 1878
name: label: maker
content: Charles Williams, Jr.
notes: label: Description
content: Telegraph repeaters amplified electrical signals in a telegraph line. Telegraph messages traveled as a series of electrical pulses through a wire from a transmitter to a receiver. Short pulses made a dot, slightly longer pulses a dash. The pulses faded in strength as they traveled through the wire, limiting the distance a message could travel. Repeaters remedied that problem by detecting a weak signal and using a local power source to re-energize and re-transmit the signal down the line.
label: Description
content: This repeater was made by Charles Williams, Jr. of Boston and used in experiments by Moses Farmer. Our records indicate that this repeater was used as evidence in suit against Western Union Telegraph Company by Farmer.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
label: See more items in
content: Telegraph Relays & Repeaters
label: See more items in
content: Communications
creditLine: label: Credit Line
content: from Sarah J. Farmer
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.181954
label: catalog number
content: 181954
label: accession number
content: 2015.0173
objectType: label: Object Name
content: telegraph repeater
label: Object Name
content: telegraph relay
physicalDescription: label: Physical Description
content: brass (overall material)
label: Physical Description
content: wood (overall material)
label: Physical Description
content: steel (overall material)
label: Physical Description
content: plastic (overall material)
label: Measurements
content: overall: 4 1/2 in x 9 3/4 in x 6 7/8 in; 11.43 cm x 24.765 cm x 17.4625 cm