Signal enhancement of the central NMR transition of quadrupolar nuclei with half-integer spin is achieved by applying a hyperbolic-secant pi-inversion (sechinv) pulse to the satellite transitions. In combination with the quadrupolar Carr-Purcell Meiboom-Gill (QCPMG) Pulse train, the sechinv pulse provides an additional signal enhancement of up to 2.7 for spin 3/2 nuclei in powdered solids. The Rb-87 NMR enhancements realized using this experiment are compared to those obtained employing rotor-assisted population transfer (RAPT) and double frequency sweep (DFS) pulse experiments on magic angle spinning (MAS) powdered samples. In every case, the sequence employing sechinv Pulses gives greater enhancements than the previously reported methods. (C) 2004 Elsevier B.V. All rights reserved.