KD-1, proximity switch, is a small device which detects visitors at close range (under 3/8-inch). Based on the detection of capacitance rather than touch, the KD-1 can be mounted behind graphics and within exhibit material up to 3/8-inch thick. Measuring approximately 5 x 2 x 1cm, this small activator comes wired with a 7ft cord and a modular plug for quick connection to Museum Technology products. It may be used in other applications as long as operating power of 12 to 24Vdc is available. The output of KD-1 is a NPN transistor which conducts to the common terminal (ground) when active. Maximum output load is 100mA at 30Vdc.