vacuümtubes
Vacuümtubes are sealed electronic components that control electric current by means of thermionic emission of electrons from a heated cathode, all contained in an airtight envelope usually made of glass, metal, or ceramic. They rely on a vacuum to allow electrons to move freely and to prevent unwanted chemical reactions. When the cathode is heated, it emits electrons that are attracted to a positively charged anode (plate). The flow of current can be modulated by grids placed between cathode and anode, enabling amplification or switching of signals. Vacuum tubes require relatively high operating voltages and generate heat, but they offer high input impedance and certain linearity advantages in appropriate configurations.
The most common forms are diodes, triodes, tetrodes, and pentodes. A diode contains only a cathode and
History and impact: vacuum tubes were developed in the early 20th century, with key milestones such as
Today, vacuümte tubes are primarily found in niche or legacy gear, high-power transmitters, and some audio equipment