Liebenröhre-Nachbildung
Réplique d'un tube de von Lieben
LRS Relay Replica
Replica made by the former glas blower Mr. Neumann from Pressler.
In the USA, the LRS relay is named after Lieben, Reisz and Strauss, the inventors of the tube.
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.
The LRS relay was used for a time as a telephone repeater in Germany.
The cathode consists of a strip of platinum, about 1 meter in length, 1 mm wide, and 0.02 mm
thick. The auxiliary electrode (grid) is an aluminum disk with 3.5 mm apertures. The small side tube contains
an amalgam, it enabled the operator to maintain the presssure in the main tube at the proper level (about 0.01 mm Hg).
Mercury vapor could be introduced when needed by heating the amalgam. The anode is a spiral of aluminum wire about
2 mm in diameter. The anode battery was 220 V, the anode current was 10-11 mA, and the cathode heating current was
about 2 A. When the tube was in operation, the bulb was filled with the blue glow of ionized mercury vapor.
Historische Glasapparate & Lehrmittel - Lutz Neumann
Video on YouTube: Betrieb einer Liebenröhre von 1913 sowie die Ermittlung des Frequenzgang
Hauteur • Height • Höhe : 34 cm • 13" 3/8
Diamètre • Diameter • Durchmesser : max. 10 cm • 4"
Deutsche Reich Patent 264554 vom 15. Oktober 1912
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