Lieben Tube

Lieben, Robert, Vienna 1906–1910
Lender: Vienna Museum of Technology
Lieben Tube
Allgemeinen Elektrizitäts-Gesellschaft, Berlin, around 1912
9 x 31 cm, ca 5 kg
Glass, metal

This was the first attempt to make an amplifier tube. It was developed from the quicksilver vapor-filled tube and was based on various forms of a gas discharge that was altered by means of a voltage applied to the sieve-like aluminum plate. This controlled the current between the anode and the cathode. The tube reacted slowly due to the rather lethargic charging of the chamber and it was only once the device later was modified through the use of a grid and high-vacuum tubes that it could be used in practical application.