A Low Cost Superconducting Frequency Counter Josephson Voltage Standard

The principal factor preventing wide use of the Josephson primary voltage standard is its cost. By reducing the cost of a HYPRES voltage standard to a level comparable with true cost of secondary standards (including the cost of calibration and low accuracy, etc.), and making it easy to use, we intend to put the Josephson voltage Standard within reach of most secondary standard users. In phase I, we intend to demonstrate that a low-cost (<$1000), reliable superconducting counter will substitute for the expensive ($22,350) room temperature 77 GHz frequency counter. In Phase II, we intend to incorporate this, and as many other cost reducing ideas as appear feasible, in a closed-cycle refrigerator-beased standard. The best way to assess the value of the cost savings attributable to use of a superconducting counter is that it should approximately pay for replacing the liquid helium dewar with a refrigerator, making the whole system much more acceptable to most potential users.