Quenched-spark transmitter in the style of Max Wien

In 1906 Max Wien developed the quenched spark gap, divided into short sections by metal plates. Cooling the system means the sparks go out faster than with a spark-gap transmitter and can be ignited faster. This reduces energy losses and enables higher frequencies. During reception, instead of cracking, you hear a high, clear sound that can be easily distinguished (sound radio transmitter).