Air Capacitors

Air Capacitors Points : Air Capacitors Air capacitors have two sets of metal plates (brass or aluminum), one set fixed and the other movable. The fixed set, spaced and connected in parallel, is mounted rigidly on to an insulating framework. The second set, also spaced and connected in parallel, is mounted on a shaft with bearings. The movable plates can be adjusted into or out of the spaces between the fixed plates. Thus the area of plates opposite to each other is increased or decreased thus increasing or decreasing the capacitance. Air capacitors are available with capacitance value ranging from a few microfarads to a few hundred microfarads and with working voltage range of 150 to 3000 volts peak. They are mainly used for radio frequency tuning.