= Spark-gap transmitter
{title2=1890s}
{wiki}
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[https://youtu.be/NyZ87wNotBg?t=57]
{title=Spark-gap transmitter at the at the The Museum of Radio and Technology Jeri Ellsworth (2017)}
\Video[https://www.youtube.com/watch?v=YSf93g0heUA]
{title=Marconi Spark Gap Transmitter Demonstration by Canada Science and Technology Museum (2012)}