Ringing

Ringing

Electricity

In electrical circuits, ringing is an unwanted oscillation of a voltage or current. It happens when an electrical pulse causes the parasitic capacitances and inductancesFact|date=May 2008 in the circuit (i.e. those that are not part of the design, but just by-products of the materials used to construct the circuit) to resonate at their characteristic frequency. Ringing artifacts are also present in square waves; see Gibbs phenomenon.

Ringing is undesirable because it causes extra current to flow, thereby wasting energy and causing extra heating of the components; it can cause unwanted electromagnetic radiation to be emitted; it can delay arrival at a desired final state (increase settling time); and it may cause unwanted triggering of bistable elements in digital circuits. Ringy communications circuits may suffer falsing.

Video

In video circuits, electrical ringing causes closely spaced repeated ghosts of a vertical or diagonal edge where dark changes to light or vice versa, going from left to right. The electron beam upon changing from dark to light or vice versa instead of changing quickly to the desired intensity and staying there, overshoots and undershoots a few times. This bouncing could occur anywhere in the electronics or cabling and is often caused by or accentuated by a too high setting of the sharpness control.

Medicine

In hearing, ringing is an endaural phenomenon in which a person hears a sound, somewhat like a pure tone, without any external acoustic stimulation. Ringing in the ears commonly follows exposure to loud noises, and is a sign of damage to the hair cells of the inner ear. Ringing in the ears is a common sort of tinnitus.

Ornithology

Bird ringing is using individually-numbered small metal leg rings placed on birds' legs to track their activity.

Telephony

Ringing current is the pulsating DC current that powers a telephone bell.

External links

* [http://www.michaeldvd.com.au/Articles/VideoArtefacts/VideoArtefactsMicrophony.html Microphony with older video cameras]


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Look at other dictionaries:

  • Ringing — Ring ing, a & n. from {Ring}, v. [1913 Webster] {Ringing engine}, a simple form of pile driver in which the monkey is lifted by men pulling on ropes. [1913 Webster] …   The Collaborative International Dictionary of English

  • ringing — index resounding Burton s Legal Thesaurus. William C. Burton. 2006 …   Law dictionary

  • ringing — adj *resonant, sonorous, resounding, vibrant, orotund …   New Dictionary of Synonyms

  • ringing — ► ADJECTIVE 1) having a clear resonant sound. 2) (of a statement) forceful and unequivocal. DERIVATIVES ringingly adverb …   English terms dictionary

  • Ringing — Gibbssches Phänomen bei einer Rechteckskurve Als Gibbssches Phänomen oder „Ringing“ bezeichnet man in der Mathematik das typische Verhalten von Fourierreihen in der Umgebung von Sprungsstellen. Entwickelt man eine Fourierreihe aus einer… …   Deutsch Wikipedia

  • ringing — [[t]rɪ̱ŋɪŋ[/t]] 1) ADJ: ADJ n A ringing sound is loud and can be heard very clearly. He hit the metal steps with a ringing crash. Syn: resounding 2) ADJ: ADJ n A ringing statement or declaration is one that is made forcefully and is intended to… …   English dictionary

  • ringing — ring|ing [ˈrıŋıŋ] adj 1.) a ringing sound or voice is loud and clear ▪ She pronounced her final words in ringing tones. 2.) a ringing endorsement a statement that is made with a lot of force in support of something ▪ a ringing endorsement of the… …   Dictionary of contemporary English

  • ringing — /ˈrɪŋɪŋ/ (say ringing) verb 1. present participle of ring1. 2. present participle of ring2. –noun 3. the ringing of a bell, telephone, etc. 4. a similar constant sound in the ears; tinnitus. –adjective 5. sounding as a bell: a ringing sound. 6.… …  

  • ringing — noun 1. the sound of a bell ringing (Freq. 1) the distinctive ring of the church bell the ringing of the telephone the tintinnabulation that so voluminously swells from the ringing and the dinging of the bells E. A. Poe • Syn: ↑ring,… …   Useful english dictionary

  • Ringing — Ring Ring (r[i^]ng), v. t. [imp. {Rang} (r[a^]ng) or {Rung} (r[u^]ng); p. p. {Rung}; p. pr. & vb. n. {Ringing}.] [AS. hringan; akin to Icel. hringja, Sw. ringa, Dan. ringe, OD. ringhen, ringkelen. [root]19.] 1. To cause to sound, especially by… …   The Collaborative International Dictionary of English

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