An instrument has been developed for direct measurement of critical current and plotting of current-voltage (I-V) characteristics of superconductors in pulse mode. For these measurements, current pulses of increasing height are applied to sample and the voltage developed across the sample is monitored using a low noise voltage measuring circuit. Different sources of error responsible for limiting accuracy of pulse measurements techniques are discussed. A compensation network has been developed

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... o reduce inductively induced voltages generated during pulse measurements, to negligible values. The instrument enables automatic critical current measurement with 1-10 V/cm criteria in pulse mode without a computer and has voltage sensitivity of 10 nV. Critical current as a function of temperature/magnetic field and I-V characteristics of Bi-2212 single crystal and Y-123 thin films have been plotted using the circuit and the results have been compared with those obtained using direct current measurements.