Cross-correlation measurements in searching for a trace of the gate voltage noise in a JFET

The trace of the gate noise voltage was successfully caught by the measurements of the correlation between the noise outputs of a pair of JFETs connected to a common gate resistor. It is shown for 2SK150 (n-channel junction FET) that the gate noise voltage is 1/f-type and its level is -142dbV2/Hz at 1Hz, and that the correlation coefficient between the gate noise voltage and the gate noise current is -1.