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It was created around 1787 an 1951
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It was created around the 1870s.
It had mostly nothing on it, it was just a receiver and a transmiter -
It was created in around 1998 and 1900.
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It was created in around 1901.
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It was created round 1907 and 1900.
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It was created around the 1950s.
It was first used in communication in the second world war -
It was created in around 1990