Bunnell pole-changer relay

Bunnell pole-changer relay

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Description
Telegraph relays amplify an electrical signal in a telegraph line. Telegraph messages travel as a series of electrical pulses through a wire from a transmitter to a receiver. The pulses fade in strength as they travel through the wire, limiting the distance a message can be sent. Relays remedy that problem by detecting a weak signal and automatically re-transmitting that signal down the line using a local power source.
Location
Currently not on view
Object Name
relay
pole changer relay
telegraph relay
Maker
Western Union Corporation
maker
J. H. Bunnell
J. H. Bunnell & Co.
Measurements
on mount: 7 1/2 in x 11 1/2 in x 8 3/4 in; 19.05 cm x 29.21 cm x 22.225 cm
w/o mount: 6 1/4 in x 9 in x 5 in; 15.875 cm x 22.86 cm x 12.7 cm
ID Number
EM.331852
collector/donor number
13-03
accession number
294351
catalog number
331852
Credit Line
from Western Union Corporation
See more items in
Work and Industry: Electricity
Communications
Data Source
National Museum of American History
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