Improvement of the accuracy of thermal converter voltage measurements for frequencies up to 50 MHz

Thermal converters with 5 V, 1000-ohm input parameters for use as transfer standards of voltage can be designed to have an ac-dc difference of less than ±0.1% up to a frequency of 50 MHz. With this high input impedance the repeatability of connection is significantly better than with a 50-ohm input impedance device. If this thermal converter is calibrated against a reference standard thermal converter having an internal Tee, it is possible to apply corrections to the transfer standard so that its ac-dc difference is known to ±0.01% and has very good repeatability