The ability of devices based on the phenomena of magnetoelastic waves, acoustic bulk waves, acoustic surface waves, and the optoacoustic interaction to fulfill the requirements for a dispersive filter for a pulse compression RADAR are reviewed. The performance and current limitations of devices that use techniques employing these effects are described. The discussion is generally limited to devices which have been operated in the frequency range above 100 MHz. For comparison, other solid-state techniques that do not employ acoustic waves which can be used to make dispersive filter are described.