Although the specific grants available change over time, the Corporation for Public Broadcasting (CPB) is always a good place to look. As of May 2010, the CPB is awarding three grants. The Greenhouse Fund, which has a rolling application, provides funding for professional development projects aimed at public television professionals and independent producers. The Program Challenge Fund, which is jointly administered by CPB and PBS, supports prime-time limited series and specials for national public television. The Digital Distribution Fund also awards grants to non-commercial educational television licensees.
Founded in 1936, the Ford Foundation has been a major source of funding for public broadcasting since its inception. The foundation offers a wide variety of grants both to organizations and to individuals. Its overall goal is to support democracy and human rights through education and independent media projects. Grants are available on a rotating basis, so check the foundation's website for more information.
If your proposal is related to the arts, the National Endowment for the Arts (NEA) is always a good place to look for grants. A large portion of its funding goes to arts education projects, including television and radio broadcasting. One of the grants, "The Arts on Radio and Television," is specifically geared toward funding the development, production and distribution of arts-related radio and television programs. In order to apply for this grant, you must have nonprofit, tax-exempt status and apply directly on your own behalf.
Ready to Learn Television is a federally funded grant for programs that increase school readiness among preschool-age children, especially by promoting literacy. The grant is available only to nonprofit organizations, including public telecommunications entities. It is particularly aimed at organizations that have proven their ability to distribute television programming on a large scale.