VGA extender

A VGA Extender is an electronic device that increases the signal strength from a VGA port, most often from a computer. They are often used in schools, businesses, and homes when multiple monitors are being run off one VGA port, or if the cable between the monitor and the computer will be excessively long (often pictures appear blurry or have minor artifacts if the cable runs too far without a booster). VGA extenders are sometimes called VGA boosters.

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*http://www.ascot-systems.co.uk/HomeProductsTrainingVGAAmplifier.htm