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Spark-gap transmitter by Ciro Santilli 34 Updated Created
The first type of device that allowed sending Morse code without wires, as opposed to the wired electrical telegraph that previously existed.
Naval communications was one of the first major applications, as you can't have wires on boats!
Wireless voice transmission came about with modulation.
Video 1.
Spark-gap transmitter at the at the The Museum of Radio and Technology Jeri Ellsworth (2017)
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Video 2.
Marconi Spark Gap Transmitter Demonstration by Canada Science and Technology Museum (2012)
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