Electronic circuits and components
This common form of solid-dielectric capacitor consists of two aluminium foils separated by a thin insulating plastic film. The entire assembly is then rolled into a tube. The capacitor is then plastic dipped in order to provide insulation and sealing against moisture. Values from 100pF to 100nF are typical.
This simple variable capacitor consists of sets of fixed and moving plates that are meshed with one another. The moving plates are driven by a rotary control shaft and the dielectric material between the plates is air. Values of 10pF to 500pF are typical.