APPARATUS FOR TRANSPORT CHARACTERIZATION OF HIGH-T-C SUPERCONDUCTORS

A full set of facilities for transport characterisation of HTS as well as a set of crucial measurements are presented which point out the possible sources of errors of the <<home-made>> apparatus. The main characteristics are the automatisation of the whole data acquisition, the appositely designed hardware and software with suitable error messages, the on-line statistical treatment of data, the possibility of on-line optimisation of the current pulses and finally the availability of quasi-static temperature conditions in the R vs. T curves. The d.c. four-point method with bipolar d.c. pulsed current is employed. The experimental techniques chosen to obtain specific metrological achievements are discussed.