Improvements have been made in the differential pulse transformer bridge which increase its inherent precision by approximately an order of magnitude and extend its range to measurements with electrolytes of twenty times the concentration previously feasible. A circuit is described which permits study of the errors introduced by polarization and self‐heating when electrolytic conductivity measurements are carried out with rectangular voltage pulses. Also described is an equipment for four‐terminal resistance measurements with single‐voltage pulses, which allows high‐field conductance measurements free from errors caused by contact resistance, self‐heating, and space‐charge accumulation; it has been applied to semiconductors.