Farmer telegraph repeater patent model
date: label: date made
content: 1856
name: label: maker
content: Farmer, Moses G.
notes: label: Description (Brief)
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 (Brief)
content: For many years inventors were required to submit models to the Patent Office when they filed for a patent. In 1856, Moses G. Farmer received U. S. patent #14,157 for his “telegraphic repeater”. This is the model Farmer submitted that shows his circuit for an improved way to retransmit telegraph signals. Prior to this invention repeaters had to be switched manually by a telegraph operator. This sometimes led to delays if the operator were otherwise occupied. Farmer's invention allowed for automatic operation of the repeater.
label: Location
content: Currently not on view
topic: label: general subject association
content: Patent Models
setName: label: See more items in
content: Work and Industry: Electricity
label: See more items in
content: Communications
label: See more items in
content: Telegraph Relays & Repeaters
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.308860
label: catalog number
content: 308860
label: accession number
content: 89797
label: patent number
content: 14,157
objectType: label: Object Name
content: telegraph receiver
label: Object Name
content: telegraph register
label: Object Name
content: telegraph relay
label: Object Name
content: telegraph repeater
label: Object Type
content: Patent Model
physicalDescription: label: Physical Description
content: wood (overall material)
label: Physical Description
content: cloth (overall material)
label: Physical Description
content: brass (overall material)
label: Physical Description
content: steel (overall material)
label: Physical Description
content: ivory (overall material)
label: Measurements
content: overall: 4 in x 10 in x 12 in; 10.16 cm x 25.4 cm x 30.48 cm