The Talbot interferometer has been shown earlier to act as an optical tapped delay-line in the time domain. The interferometer is based on the self-imaging effect. It consists of two gratings separated by a multiple of the self-imaging distance. Here, we determine its temporal behaviour experimentally. First, the impulse response is measured directly in the time domain by means of femtosecond pulse technology and second, by spectroscopy we measure its power spectrum. Results confirm earlier theoretical considerations.