Numerous concise recommendations appear in the notebook volume bearing the number 401.0-B. Each recommendation is dated, and the most recent revision is shown in the table of contents. These Recommendations are developed for conventional near-Earth and deep-space missions having moderate communications requirements. The current issue adds new recommendation 2.4.23, Modulation Methods at High Symbol Rate Transmissions, Earth Exploration Satellites (EES) 25.5, 27.0 GHz Band, Space-to-Earth.