An undergraduate experiment is proposed to facilitate the understanding ofthe basic principles related to radar systems and signal analysis. ADoppler-effect radar has been installed and used to measure the velocitiesof a target under different conditions. This system features the use of alow-power generator and a general purpose data acquisition card. Theanalysis of the measured IF (intermediate frequency) voltage has been made by using the fast Fouriertransform in order to illustrate the relevance of the basic spectraltechniques for the characterization of weak signals in noisy environments.