A vacuum tube, electron tube,[1][2][3] valve (British usage), or tube (North America)[4] is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied.
A vacuum tube, electron tube,[1][2][3] valve (British usage), or tube (North America)[4] is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied.