• Record the characteristic for a thermionic diode at different cathode heater voltage
• Identify the space charge and saturation regions
• Confirm the Schottky-Langmuir law
Experiment description: ..
In a thermionic diode, free electrons carry a flow of current between the heated cathode and the anode when a positive voltage is applied between the cathode and anode. The current increases along with the voltage until a saturation point is reached. However, if the voltage is negative, the current is zero.
The relationship between the anode current IA and the anode voltage UA is investigated as the characteristic of the diode. The reverse-bias region, the region where current begins to flow, the space charge region, and the saturation region are identified.
The Schottky-Langmuir law is verified by the IA-UA-relation within the space charge region.
![Experiment: Thermionic Diode (230 V, 50/60 Hz), 8000656 [UE3070100-230], Electron tubes](/imagelibrary/UE3070100-230/UE3070100-230_01_Experiment-Thermionic-Diode-230-V-5060-Hz.jpg)
![Experiment: Thermionic Diode (230 V, 50/60 Hz), 8000656 [UE3070100-230], Electron tubes](/thumblibrary/UE3070100-230/UE3070100-230_01_1200_1200_Experiment-Thermionic-Diode-230-V-5060-Hz.jpg)
