The characteristics and calibration of a microchannel-plate-based resistive-anode position-sensitive detector (PSD) are reported. Factors affecting the spatial uniformity of the fast rise-time timing signals and the position-dependent performance are discussed. When two such detectors are used for (e,2e) coincidence measurements, the detection efficiency of the PSDs must be uniform to within 5% for reliable quantitative comparisons of data acquired on different sections of the PSD. The relative efficiency in coincidence mode reflects the single detector efficiency uniformity. Such an apparatus was used to measure argon triple differential cross sections (TDCS) to determine the validity of the distorted wave Born approximation (DWBA) quantum scattering model. Relative to the argon 3s TDCS, the simultaneously acquired 3p TDCS is smaller than the DWBA prediction by a factor of 1.15+/-0.05. (C) 1997 American Institute of Physics.