Usually on the Public Broadcasting System during a scientific or educational program they say “Made possible by a grant from the Corporation for Public Broadcasting”.
The CPB site is full of information on PBS.
Is the CBP and PBS the same thing or just intimately related but distinct entities?
The Corporation for Public Broadcasting is a private non-profit, founded by Congress in the 1960s. They provide grants to PBS, NPR, ITVS and a number of other places. They receive both private funding and appropriations from Congress.
Another example of CPB’s activities is the partial funding of the nation’s 750 or more) “public radio stations”, each of which is privately owned, licensed and funded. in the 2004 budget, IIRC, CPB disburses a total of $83 million to radio stations (ca. 15% of their operating budgets) That may just be the total federal funds they disburse, however. I don’t have a copy of the annual report handy, and they do have (at least through partnerships with philanthropic organizations like the Annenberg Foundation, and possibly directly) significant private funding.
NPR (National Public Radio) doesn’t actually own or operate a single radio station, and especially after the flak over gov’t funding a few years ago, not one dollar of NPR’s $100 million budget comes from direct federal funding. CPB funds the development and production of documentaries and independent projects, which may air on public radio radio stations. Stations pick and choose original programming from the offerings of NPR, PRI, and various syndicators and production groups (paying per show) and also create their own programming in-house.
I realize that you were asking about TV, but I thought the radio side might illustrate some of CPB’s operations. For example, CPB might (I don’t know if they currently do) fund a grant to CTW (Children’s Television Workshop) but “Sesame Street” and its profits still belong to CTW, and are not directly beholden to any governmental agency.