Potentiometer Arrangement for Measuring Microvoltages at Radio Frequencies

The arrangement described enables voltages down to about 0.1 microvolt to be measured to within about one percent. The resistance units are wound non-inductively on a toroid so as to reduce the lengths of connecting wires to a minimum. Up to frequencies of 3×{}10⁶ cycles, the impendance of such a unit is less than one per cent higher than the pure resistance. The potentiometer is built compactly to minimize capacity effects and for convenient use in the field.