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by Ray DeCosta

Q. My keyboard seems to have a problem. Sometimes when I'm typing, a key keeps repeating a character all the way across the screen. Then I have to pound away on the offending key until it stops. What is wrong?

A. Assuming you have a mechanical keyboard, you have a classic case of too much dirt having infiltrated into the keyboard mechanisms. Also known as "PS/2" or "click-and-clack" keyboards, this style does tend to collect dirt, dust or pet hair which interferes with its proper operation. These keyboards get their name from using a PS/2 connector which can be identified by its having a circular 6-pin layout.

There is another type of keyboard which is commonly called a "USB" or "membrane" keyboard. This style relies on a different technology that is much more resistant to this problem. This keyboard will have a standard USB connector, rectangular in layout.

A safety note is in order at this time. Do not attempt to connect or disconnect a PS/2 keyboard to or from a computer that is turned on. It is quite possible that doing so could damage your computer's main board due to voltage spikes. Always shut your computer all the way down (power off) before changing your PS/2 keyboard. This warning in not applicable to USB keyboards which can be plugged in or out of the computer at any time.

The best way to clean a PS/2 keyboard is to disconnect it from your computer, after powering everything down, and taking it outside. Use a can of compressed air (available at any big-box or office supply store) and thoroughly blow out all the debris that has accumulated. Masses of pet hair, cookie crumbs and other items will all make their presence known.

Do not be tempted to take the keyboard apart to "really" clean it. Most PS/2 keyboards will quickly reward you for your efforts by providing you with an extensive puzzle to reassemble. This puzzle will consist of hundreds of parts such as key caps, springs, and many other mysterious items.

Published: Courier 12/2/12 - Page 3C