Yes, employing a directional antenna can potentially be a solution to address a second adjacent channel waiver issue. Directional antennas are designed to focus the radiation pattern of the transmitted signal in specific directions while reducing it in others. By carefully configuring a directional antenna, it may be possible to minimize interference with neighboring stations on second adjacent channels, thus improving the chances of obtaining a waiver for such a setup. However, the feasibility and success of this approach would depend on various technical and regulatory factors, and it may require consultation with experts and relevant authorities.