Josephon Array Voltage Calibration System: Operational Use and Verification

A New Josephson Array System Now Maintains The U. S. Legal Volt On A Weekly Basis. The Accuracy Of The I-volt Level Of This System Was Verified To Within 0.03 Ppm In Multiple Tests Against Two Independent Resistive Dividers. The Precision In The Verification Was -limited By Uncertainties In The Divider Instruments.