A degauss causes a magnetic field inside the tube to oscillate rapidly, with decreasing amplitude.
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Similarly shaped demagnetizers used magnets to degauss the deck, which kept sound from becoming distorted.
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The new monitor has no option to degauss it manually.
From the en.wikipedia.org
A degauss option is also usually available for manual selection in the operations menu in such appliances.
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Many televisions and monitors automatically degauss their picture tube when switched on, before an image is displayed.
From the en.wikipedia.org
Shaking wires increase the magnetic permeability, while the permanent degaussing wires are applied to all surfaces of the inner main layer to degauss the surfaces.
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More examples
Demagnetize: make nonmagnetic; take away the magnetic properties (of); "demagnetize the iron shavings"; "they degaussed the ship"
(degaussing) the process of making a (steel) ship's hull nonmagnetic by producing an opposing magnetic field
Degaussing is the process of decreasing or eliminating an unwanted magnetic field. It is named after Carl Friedrich Gauss, an early researcher in the field of magnetism. ...
To reduce or eliminate a magnetic field, especially from the hull of a ship, or from a computer monitor
(Degaussing) Magnetic stripe data erasure.
(Degaussing (of monitor)) An operation that is activated by pressing the DEGAUSS button on a high-resolution color monitor. Residual magnetism and charge are removed by this operation so that the electron beam can land on the proper phosphor and render correct colors.
(Degaussing) A process of destroying computerized data by leaving the domains in random patterns with no preference to orientation, which then renders previous data unrecoverable. ...
(Degaussing) The process of demagnetizing (removing the magnetic field) of a monitor that can build up over time or occur from external sources, to remove the color or picture distortion caused by the field.
(Degaussing) This function removes magnetism from the CRT, on some models this is activated automatically once the power is switched on. Most models include this function within the user OSD menu.