A pulsed current technique for measuring the critical transport properties of superconductors as a continuous function of current or temperature is described. Greatly reduced sample heating permits investigation of both the ‘‘weak link’’ and intrinsic properties of granular superconductors. Results obtained for various high Tc oxide superconductors provide an example of the technique’s application. Both intergranular and intragranular critical current densities are extracted from the data. Current-voltage measurements using the pulse method are corroborated by traditional dc measurements.

: Samples of the bismuth based high temperature superconducting family Bi2Sr2Can-1CunO2n+4 delta have been prepared and characterized by x-ray diffraction, and temperature-dependent resistivity and thermoelectric power measurements. Both of the high temperature superconducting phases reported in the literature, with transition temperatures near 80K and 110K, have been observed. Evidence from thermoelectric power measurements is presented which shows that this family of ceramic superconductors has contributions to the electrical transport that is both electron-like and hole-like. However, all of the superconducting transitions observed involve hole-like states. Thin films, superconductivity, ceramic, Copper oxides, Bismuth compounds, Strontium compounds, Calcium, Reprints.