The Electrical Properties of the Probe under Different Loading Frequencies

Abstract

A testing circuit of probe is designed to research the electrical properties of the probe under different loading frequencies. Sinusoidal signals of different frequencies are produced by Tektronix AFG3102 signal generator, and DSOX2022A Oscilloscope is used to measure the probe voltage,constant resistance voltage and the source voltage, so the phase between the probe voltage and constant resistance voltage can be calculated. Assumed the constant resistance is a pure resistance. Since the circuit is connected in series, so the phase between the probe voltage and the probe current can be calculated. The result reveals that the probe shows resistive when the phase between the probe voltage and the probe current is 0 ° within 200 KHz frequency. Beyond 200 KHz the phase between the probe voltage and the probe current increases to 60 ° and then declines to a steady value 40°, which shows that the probe is inductive.