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Freir polar relay

Freir polar 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.
Object Name
relay
polar relay
telegraph relay
Maker
Western Union Corporation
Measurements
overall: 5 in x 9 in x 4 in; 12.7 cm x 22.86 cm x 10.16 cm
ID Number
EM.332184
collector/donor number
100-877
accession number
294351
catalog number
332184
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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