How to Degauss a Computer Monitor
To degauss something means to remove, or at least drastically reduce, a magnetic field. Magnetic interference was so common with CRT displays that degaussing coils were built into these types of screens to occasionally remove this interference. Most people no longer have those old “tube” monitors, so this isn’t a common task these days. The large, high resolution, inexpensive flat LCD screens of today work completely differently, do not suffer from magnetic interference, and so never require degaussing. There are lots of reasons why a computer screen might have some kind of color problem, but if you have an old CRT-style monitor, especially if the discoloration is mostly near the edges, degaussing will probably fix it and should be your first troubleshooting step. Here’s how to do it:
More About Degaussing & How to Prevent It
The best way to prevent the magnetic field disturbances that caused this discoloration on the monitor you just fixed, is to check around the screen for sources of magnetism. Usually, this is something like unshielded speakers, power sources, and other major electronics. If the discoloration doesn’t improve, continue to the next step. The degauss button will most likely be accompanied by a picture similar to a horseshoe, representing that classic “horseshoe magnet” shape. Some degauss buttons actually are a horseshoe icon (versus a standard, round button). No, degauss button? Let’s keep trying… Still no luck? Some monitors hide the feature even deeper. Scroll through these options and locate the degauss option, which you’ll select with whatever selection button you’ve been using to “enter” other commands/options in the monitor’s on-screen menu. For example, your monitor might have the option here: MENU > OPTION > DEGAUSS. Yes, of course, magnets cause this as well! Leave those for the refrigerator or the science project in the other room. As much of a problem as degaussing sounds like with monitors and televisions, it may be something you actually want to do if you have data on a hard drive that you want to erase forever. Handheld degaussing wands and desktop degausser machines apply a super-strong magnetic field to a hard drive, destroying any data stored on it. Actually, wiping a drive is cheaper and equally effective, but degaussing is another option on a very short list of completely effective ways of erasing a hard drive. The word degauss comes from the word gauss, which is the measurement of a magnetic field, named after famed physicist and mathematician Johann Carl Friedrich Gauss who lived in Germany in the late 18th and early 19th centuries.
