A piece of electronic test equipment consisting of several precision resistors and selector switches. By connecting the resistance decade into a circuit and setting the selector switches in the proper positions, any required amount of resistance can be put into a circuit.

The resistance decade gets its name from the increments of resistance that can be selected. One switch can select resistances between 0.0 ohm and 0.9 ohm, in ten steps (a decade of steps) of 0.1 ohm each. The next switch can select resistances between 1.0 and 9.0 ohms. The other switches can select between

10.0 and 90.0, 100.0 and 900.0, and 1,000 and 9,000 ohms. With five switches, any amount of resistance between 0.1 ohm and 9,999.9 ohms can be put into a circuit.