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Creed polar relay

Creed 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
polar relay
relay
telegraph relay
maker
Creed & Co., Ltd.
Measurements
overall: 5 1/2 in x 6 in x 3 in; 13.97 cm x 15.24 cm x 7.62 cm
ID Number
EM.332135
patent number
172717
collector/donor number
100-891
accession number
294351
serial number
321
catalog number
332135
Credit Line
from Western Union Corporation
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Work and Industry: Electricity
Communications
Data Source
National Museum of American History
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