A MULTICHANNEL AVERAGER TECHNIQUE FOR CURRENT-VOLTAGE MEASUREMENTS INHIGH-T-C SUPERCONDUCTORS

A computer-controlled technique was developed to measure the current-v oltage dependences in high-T-c superconductors. The system is based on the multichannel averaging technique. The current through the sample follows a triangular bipolar waveform and is measured by a data acquis ition board to be used as an index to a memory array in which the samp le voltage is to be averaged. Applying this principle, the noise level present in the sample voltage virtually does not matter. The desired signal will build up, from the noise, proportional to the square root of the number of scans. The main advantage of this technique is the si mple and inexpensive hardware requirements.