control electrode การใช้

There is a third electrode charged negatively with respect to the cathode, called the Wehnelt or control electrode.
A hot cathode is at an advantage, as ionization of the gas is made easier; thus, the tube's control electrode is more sensitive.
Other devices that have control electrodes as well as acting as unidirectional current valves are used where more than simple rectification is required e . g ., where variable output voltage is needed.
This places the control electrode at a maximum distance from the space-charge region surrounding the filament, minimizing the amount of electrons collected by the control electrode, and thus minimizing the input current.
This places the control electrode at a maximum distance from the space-charge region surrounding the filament, minimizing the amount of electrons collected by the control electrode, and thus minimizing the input current.