A new and improved design of the JV current shunts for 30 to 100 mA has been developed. The new shunts use surface-mount resistors mounted in a star configuration. AC-DC difference less than 3 muA/A at 100 kHz and less than 5 muA/A at 300 kHz has been achieved. Calculated and measured values agree very well.

Fifteen National Metrology Institutes have participated in DC voltage ratio comparison CCEM-K8. The method followed to normalize the participants' results, the calculation of the key comparison reference values and the comparison results are reported for the two mandatory ratios of the comparison, 1000 V/10 V and 100 V/10 V.

Connecting thermal current converters (TCC) in series for calibration of current ac-dc difference, attention has to be paid to the various current leakages that may occur. Calculations indicate leakage error less than 2*10-6 at frequencies up to 100 kHz. Measured values show that error contributions are less than 1*10-6 at 100 kHz, which is well below the predicted value

A precision set-up and method for calibrating the division ratios of a resistive divider for DC-voltage in the range 10 V to 1000 V is described. The method requires equipment commonly available in most standard laboratories. Uncertainties better than 3/spl times/10/sup -7/ (k = 2) in the ratio is achieved.

Justervesenet (JV) have developed two set-ups for programmable Josephson arrays. One set-up for arrays operating up to 20 GHz and one for frequencies from 72.5 GHz to 76 GHz. The set-ups and results from the characterisation of three different programmable arrays of the intrinsically shunted SINIS type are presented. The arrays were a /spl sim/20 mV array with 512 junctions binary divided into 8 segments operating from 10 GHz to 20 GHz and two 1 volt arrays operating at 72.5 to 76 GHz with 8192 junctions binary divided into 14 and 6 segments. All arrays were manufactured by the Physicalisch-Technische Bundesanstalt (PTB) in Germany.

Automatic set-ups for comparison of AC-DC transfer standards and generation of absolute ACV have been developed. The set-ups are controlled by modern Microsoft Windows NT compatible software.The methods used and the set-ups are successfully tested in three international intercomparisons. Results are given.