Stepped Attenuator

A type of variable attenuation device using a switch with two or more (sometimes many more) contact positions, each with different amounts of resistance applied. Usually the switches are set up with a gradually increasing amount of resistance on each switch position, which yields a stepped attenuator that gradually lowers a signal level at its output for each subsequent position of the switch. In most cases these are rotary devices, and so they look like a standard potentiometer from the outside, but the rotation isn’t smooth and continuous like a pot. Instead there are several “detents,” which are the different position of the switch making contact. Stepped attenuators can often be built with higher quality resistors than comparably priced pots, and they tend to last longer, in part because the switches can be made to provide a more robust contact than the strip of resistive material and wiper used in pots. And while they don’t allow for continuous/smooth adjustments over their range they do provide an easy means to recall exact gain settings.