What Is an Air Variable Capacitor?
An air variable capacitor is used to adjust capacitance in electrical circuits. It’s commonly used in radio tuning and for adjusting resonant frequencies in high-frequency circuits. This type of capacitor varies its capacitance by moving metal plates (electrodes) within an air gap, which serves as the dielectric medium.
The capacitance depends on the plates’ area, the distance between them, and the dielectric constant. With air as the dielectric, its constant nature means capacitance changes are mainly due to the plates’ relative positions. Thus, adjustments in plate spacing or area directly alter the capacitor’s capacitance.
Air variable capacitors are prized for their low losses, making them ideal for high-frequency applications. Their ability to be precisely adjusted ensures accurate tuning capabilities.