We report on the measurements of quadrupolar splittings and spectral densities in the mesophases of a partially deuterated smectogen 4-n-butoxybenzylidene-4’-n-octylaniline-2,3,5,6,-d(4) at two different Larmor frequencies. A broad-band multiple-pulse sequence was used to simultaneously measure the Zeeman and quadrupolar spin-lattice relaxation times. Using a model that combines molecular rotational diffusion of an asymmetric rotor and order director fluctuations, the measured spectral densities for the ring and C-alpha deuterons in the nematic and smectic A phases were accounted quantitatively. The contributions from director fluctuations were taken to second order for both J(1)(omega) and J(2)(2 omega). A global target approach was used to derive the motional parameters and a molecular prefactor for director fluctuations. It was found that the activation energy for spinning motions is lower than that for tumbling motions of the liquid crystal molecule.