From the longer Wikipedia page 
The National Public Broadcasting Archives (NPBA) – housed as part of the Broadcasting Archives at the University of Maryland – preserves the history of American non-commercial broadcasting materials. It is housed at the University of Maryland, College Park in Hornbake Library. NPBA serves as a living reminder of the cultural and intellectual continuity of the effort to make television something more than commercial networks can provide. Its mission is to work with the primary national entities of American noncommercial broadcasting to identify records and programs of historical value and to serve as a repository for those materials. Its collection is open to the public.
NPBA was initiated by educator and former PBS board member Donald R McNeil (1923-1996). Citing the language of the Public Broadcasting Act of 1967 that the primary entities of public broadcasting will "establish and maintain a library and archives of non-commercial educational television and radio programs and related materials," McNeil convinced the chief officers of the Corporation for Public Broadcasting, the Public Broadcasting Service, National Public Radio and the Association of America's Public Television Stations to launch a cooperative effort to gather in one place the historical record of American public broadcasting. The University of Maryland Libraries agreed to serve as the academic host for the effort and the Archives was officially inaugurated June 1, 1990.
The website is