In this Letter, we describe a simplification of traditional NMR diffusion experiments suitable for the case of time dependent diffusion coefficients. It is shown that by setting the experimental attenuation parameter b = gamma (2)g(2)delta (2)t(d), where td is the diffusion time, to a fixed value, it is possible to observe the characteristic variation of the normalized echo amplitude in restricted diffusion conditions and to construct the experimental curve D(t(d))/D-0 without actually performing all the measurements of the diffusion coefficient at the various times. This yields dramatic experimental time reduction.