| Capacitors are very common components in | | | | capacitors are not very stable and have high losses, |
| electronic circuits and are second only to resistors as | | | | though this is not serious in their usual applications. |
| a circuit element in electronics and a large assortment | | | | Capacitors are designed to withstand a certain |
| is usually found in every electronics workshop. They | | | | maximum voltage and are close to ideal if the voltage |
| are used in filters, both in power-supply filters and in | | | | does not vary too rapidly, and is not excessive. |
| signal filters, often in connection with operational | | | | Electrolytic capacitors are probably the most sensitive |
| amplifiers. | | | | to temperature extremes. The oxide layer grows |
| Capacitors are important in integrated circuits, and | | | | with one polarity, but is dissolved with the other |
| may be made from metal or poly silicon films with | | | | polarity, so electrolytic capacitors are polarized, and |
| silicon dioxide dielectrics on silicon. They are used in | | | | must be connected the right way round in a circuit. |
| several different ways in electronic circuits including | | | | For large capacitances, the thin, chemically-deposited |
| sometimes to store a charge for high-speed use. | | | | dielectric layers of the electrolytic capacitors are the |
| They are very common elements and are one of the | | | | choice. |
| three basic electronic elements along with resistors | | | | At the present time, air-dielectric tuning capacitors |
| and inductors that make up all passive electrical | | | | are not common, having been replaced by smaller |
| circuits. Generally they are cylindrically shaped and | | | | capacitors with mica or plastic dielectrics. |
| have 3/8 brass studs for connections to flat bar or | | | | Filter capacitors are common in electrical and |
| other heavy conductors, and can be found in many | | | | electronic work, and cover a great number of |
| electrical and electronic devices such as the flash in a | | | | applications. |
| camera. Ceramic capacitors are another old favorite, | | | | Experts say that if capacitors are not made right, |
| relying on the very high dielectric constants of | | | | they start to deteriorate after three or four years, |
| ferroelectric ceramics. Unfortunately, ceramic | | | | rather than lasting the expected seven years. |