Dynatron
The Dynatron is a special design of a historical electron tube with three electrodes , which has a special feature in its current-voltage characteristic curve with a negative differential resistance . As a result, it can be used to generate electrical oscillations in the context of an oscillator circuit . The Dynatron was developed by Albert W. Hull in 1915 .
construction
The Dynatron consists of a hot cathode arranged centrally on the inside , which is surrounded on the outside by two anodes . The internal anode is pierced with holes and, when in operation, is at a higher electrical voltage than the external second anode. Due to the arrangement of the two anodes and their voltage distribution, the secondary emission of electrons in one area of the characteristic curve results in the desired negative differential resistance, which can be used in oscillator circuits , the Dynatron oscillator , to generate vibrations.
The electron tube known as "Pliodynatron" represents an extension. An additional fourth electrode, a control grid , is attached between the hot cathode and the inner first anode. With the aid of this control grid, the frequency generated in the oscillator circuit can be influenced. In principle and structure, the pliodynatron represents a tetrode , whereas with conventional tetrodes the secondary emission of electrons at the anode, which is desired by Dynatron, is undesirable.
literature
- Friedrich Benz: Introduction to radio technology . 3. Edition. Springer, 1944, p. 426 .
Web links
- Radio Museum: Dynatron . Retrieved February 22, 2013 .
Individual evidence
- ^ Albert W. Hull: The Dynatron: A Vacuum Tube Possessing Negative Electric Resistance . In: Proceedings of the Institute of Radio Engineers (IRE) . tape 6. , No. 1. , 1918, ISSN 0731-5996 , p. 5 - 35 , doi : 10.1109 / JRPROC.1918.217353 .
- ↑ Patent US1387984 : Negative Resistance. Filed August 30, 1915 , published August 16, 1921 , applicant: General Electric Company, inventor: Albert W. Hull.