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  2. Flicker (light) - Wikipedia

    en.wikipedia.org/wiki/Flicker_(light)

    In visual perception, flicker is a human-visible change in luminance of an illuminated surface or light source which can be due to fluctuations of the light source itself, or due to external causes such as due to rapid fluctuations in the voltage of the power supply (power-line flicker) or incompatibility with an external dimmer.

  3. Noise (video) - Wikipedia

    en.wikipedia.org/wiki/Noise_(video)

    Noise, static or snow screen captured from a blank VHS tape. Noise, commonly known as static, white noise, static noise, or snow, in analog video, CRTs and television, is a random dot pixel pattern of static displayed when no transmission signal is obtained by the antenna receiver of television sets and other display devices.

  4. Electrical ballast - Wikipedia

    en.wikipedia.org/wiki/Electrical_ballast

    [1] [3] To prevent this, fluorescent tubes are connected to the power line through a ballast. The ballast adds positive impedance (AC resistance) to the circuit to counteract the negative resistance of the tube, limiting the current. [1] Several American magnetic ballasts for fluorescent lamps. The top is a rapid start series autoregulator ...

  5. Ghosting (television) - Wikipedia

    en.wikipedia.org/wiki/Ghosting_(television)

    A simulated example of severe ghosting in an analog TV broadcast. In television, a ghost is a replica of the transmitted image, offset in position, that is superimposed on top of the main image. It is often caused when a TV signal travels by two different paths to a receiving antenna, with a slight difference in timing. [1]

  6. Hydrargyrum medium-arc iodide lamp - Wikipedia

    en.wikipedia.org/wiki/Hydrargyrum_medium-arc...

    To power an HMI bulb, special ballasts act as an ignitor to start the arc, and then regulate it by acting as a choke. Two types of ballasts exist: magnetic and electronic (square-wave or flicker-free). Magnetic ballasts are generally much heavier and bulkier than electronic ballasts, as they consist primarily of a network of large inductors ...

  7. The 116 Best Kids Books of All Time - AOL

    www.aol.com/116-best-kids-books-time-212400552.html

    Bunnicula by James and Deborah Howe “Listen, this book by James Howe STILL makes me laugh out loud,” says Charlie Schumann, assistant manager and resident children’s lit enthusiast at City ...

  8. Electromagnetic interference - Wikipedia

    en.wikipedia.org/wiki/Electromagnetic_interference

    Test methods and limits were based on CISPR publications, although similar limits were already enforced in parts of Europe. [ 5 ] In the mid 1980s, the European Union member states adopted a number of "new approach" directives with the intention of standardizing technical requirements for products so that they do not become a barrier to trade ...

  9. Flicker (screen) - Wikipedia

    en.wikipedia.org/wiki/Flicker_(screen)

    The flicker of a CRT monitor can cause various symptoms in those sensitive to it such as eye strain, headaches [9] in migraine sufferers, and seizures in epileptics. [10]As the flicker is most clearly seen at the edge of our vision there is no obvious risk in using a CRT, but prolonged use can cause a sort of retinal shock where the flickering is seen even when looking away from the monitor.