or another form of magnet sitting too close to the monitor, bumping the monitor very
hard, or sitting on top of the PC’s system unit over the power supply.
The remedy to magnetization of the CRT is a process called degaussing, which is a
term derived from gauss—a measure of magnetic force. Most better monitors have a
built-in degaussing circuit that neutralizes the CRT’s magnetization with a coil of wire
inside the monitor. The degaussing circuit is activated by either a manual switch or auto-
matically through the monitor’s controls.
On monitors with a manual degauss switch, pressing the switch will neutralize the
magnetization problems of the monitor. Over degaussing a monitor can hurt it; so don’t
just keep pushing the degauss button to solve what may be display problems. The degauss
process involves some clicking and buzzing and takes only a few minutes to complete.
Most newer monitors perform an automatic degauss process when they are powered
up. The static buzz and click you hear when the monitor is powered on is the degaussing
circuit neutralizing any magnetization build up. If the built-in degaussing circuits of the
CRT do not clear u pthe magnetization problem, I recommend taking the monitor to a
repair shop for manual degaussing with a special degaussing tool.Screen Savers
Whenmonochromemonitorswerethestandard,screensaversoftwarebecamenecessary
to keep the electron beam on a monitor from burning a static image into the phosphor. If
the monitor screen became idle with an image on it, the CRT would continually refresh it
until the phosphor burned the image into the surface of the CRT screen. This was called
ghosting and was a real threat on monitors that were idle with a static display for long
periods of time. Take a look at the monochrome displays at the airport some time.
Screensaversoftwarekeptthescreenchanginganddidnotletthesameimageremain
on the screen long enough to burn into the glass. On modern color monitors, a screen
saver really does nothing to hel pthe monitor as there is little chance of the pixels burning
their image into the CRT display. Screen savers are primarily entertainment these days.
However, a screen saver can be a first-line security device to kee p prying eyes from viewing
your work. Most screen saver systems can be assigned a password that controls who can
deactivate the screen saver and access the PC. On a Windows system, the screen saver
password is set on the Display Properties window, as shown in Figure 16-16.Monitor Maintenance
The life span of a PC monitor, assuming the user wishes to keep using it, should be be-
tween five and eight years. In fact, the monitor is the one part of the PC that holds its
value over the life the PC. Monitors cost about the same as they did three to four years
ago, and as long as the monitor is still doing its job, there is little sense in replacing it. In
most situations, the monitor is purchased along with the PC and stays with it as long as
both are working.Chapter 16: Monitors and Displays^397