COMPARISON OF PRECISION AC AND DC MEASUREMENTS WITH THE QUANTIZED HALL RESISTANCE

The quantized Hall resistance R(H)(2) was compared with various 100 kOMEGA ac resistance standards. The measurements were performed with an 8:1 four terminal-pair divider bridge at a frequency of 1592 Hz. The 100 kOMEGA resistances were previously calibrated using the PTB ohm chain starting at the dc side with the same quantum Hall resistance. The mean ac value of the quantized Hall resistance was 12 906.4017 OMEGA with a relative standard deviation of 0.14 . 10(-6) after ten measurements. The total uncertainty, which is mainly determined by the ac bridge, was about 3 . 10(-6).