A variable capacitor is a capacitor whose capacitance may be intentionally and repeatedly changed mechanically or electronically. Variable capacitors are often used in L/C circuits to set the resonance frequency, e.g. to tune a radio (therefore it is sometimes called a tuning capacitor or tuning condenser), or as a. In mechanically controlled variable capacitors, the distance between the plates, or the amount of plate surface area which overlaps, can be changed. The most common form arranges a group of semicircular metal. The variable capacitor with air dielectric was invented by the engineer. He received a patent for the invention on 13 December 1893. Variable capacitance is sometimes used to convert physical phenomena into electrical signals. • In a capacitor (commonly known as a ), the diaphragm acts as one plate of a capacitor, and vibrations. • • • Multiple sectionsVery often, multiple stator/rotor sections are arranged behind one another on the same axis, allowing for several tuned circuits to be adjusted using the same control, e.g. a preselector, an input filter and the corresponding. Voltage tuned capacitanceThe thickness of the depletion layer of a reverse-biased semiconductor varies with the DC voltage applied across the diode. Any diode exhibits this effect (including p/n junctions in transistors), but devices specifically sold. 1. ^ A makeshift version of this design, using two tin cans with slightly different diameter isolated by cardboard, has been used to make variable capacitors in emergencies, e.g. by concentration camp inmates.2. While mechanical variable capacitors have been.
