File:Spark gap wireless station 1910.jpg

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Summary

DescriptionSpark gap wireless station 1910.jpg	English: A typical amateur wireless telegraphy radio station from 1910. It consists of a spark-gap transmitter (on right) which generates radio waves with an electric spark, and a crystal radio receiver (on left), connected through a "transmit/receive" switch on the wall to a large outdoor wire antenna. When sending, the transmitter is turned off and on by the operator with a telegraph key on the table to produce different length pulses of radio waves, to communicate text messages in Morse code.
Date	1910
Source	Retrieved December 5, 2008 from George Washington Pierce (1910) Principles of Wireless Telegraphy, McGraw-Hill Book Co., New York, p. 322, fig. 231 on Google Books
Author	George Washington Pierce

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Public domain	This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.	United States
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