The characteristics of band-limited random noise are employed to measure the signal transmission properties of non-coherent pulse radar receiving systems used for evaluating back-scatter signals from the ground,sea and precipitation clutter targets. a scheme using a calibrated microwave noise generator source and amplitude distribution and spectrum analysing equipment is employed, as both clutter and noise signals can be characterized by their amplitude distributions and spectra. theoretical and measured results for a radar receiving system fitted with a logarithmic amplifier are compared and the effect of distortions explained