Abstract: A self-powered electrical clamp meter measures AC voltages in the range of 6 volts to 600 volts and AC currents in the range of 1 ampere to 300 amperes, and receives operating power from the source of the voltage or current being measured. The clamp meter employs first and second rectifier circuits. One rectifier generates rectified AC power from an AC voltage signal supplied by a voltage probe, and the other rectifier generates rectified AC power from an AC current signal supplied by a current probe. First and second regulator circuits generate regulated DC power from the rectified AC power, and corresponding scaling circuits generate first and second scaled voltage signals whose respective amplitudes are proportional to the output of the corresponding rectifier. A switch selects the first scaled voltage signal when a voltage is being measured, and the second scaled voltage signal when a current is being measured.