One less obvious, but nonetheless true, example of the phenomenon has occurred since the 1980s in American public television. From the origins of the medium in the late 1950s, stations, who were then affiliated with
National Educational Television, the precursor to the current
PBS, served two specific audiences: first, they provided, on weekdays, instructional programming for children used in school classrooms, to supplement traditional curricula; second, they served adults (on evenings and weekends) by scheduling shows that were alternatives to the fare available on commercial broadcasting, such as theatrical plays, classical music concerts, literary dramas, and serious public affairs initiatives like investigative reporting and civil discussion of political matters, things that had been mostly abandoned by the commercial networks with the end of the
Golden Age of Television in and around 1960. Beginning with the
Public Broadcasting Act of 1967, the Federal government, along with those of most U.S. states, invested in production and distribution of such programming via NET/PBS and the construction of a large number of new stations. The political climate of the time was decidedly
liberal and thus supportive of generous governmental funding of the medium, which developed its institutions accordingly.
However, the 1970s saw a political turn
rightward, increasingly suspicious of Federal programs especially, and originally-anticipated steady increases in public taxpayer support did not materialize, leaving the new PBS and its stations with significant monetary gaps that had to be filled by other sources. "
Pledge drives," at least an annual occurrence on stations, emerged in the mid-1970s to address cutbacks from the
Corporation for Public Broadcasting that occurred due to political changes and the economic recessions of that period; members of the general public would donate money to the station in exchange for certain privileges. Also, stations and program producers began to cultivate so-called "underwriting" (a modified form of advertising that did not interrupt shows in progress) from businesses, particularly large corporations who were then motivated by a sense of
noblesse oblige to their communities and the country at large (in later years, these grants would become more targeted toward certain genres, raising suspicions by critics that they constituted
de facto commercial advertising). This generated another large source of revenue. Some stations went so far as to stage week-long "auctions" of merchandise or services donated by retailers and other businesses, to which viewers would place "bids," from which the winner would receive the item or service in exchange for a donation to the station; these were quite successful in many markets from the 1970s through the 2000s.
In order to attract audiences who would donate to stations, which, in turn, purchased programming from other stations and producers in the PBS system, program managers felt increasingly that it was necessary to reduce the proportion of cultural and informational shows on the adult schedule, in order to appeal to a wider audience than a small, highly-educated cohort. This especially became the case during pledge drives, which were imagined to be times when non-regular viewers could be appealed to with special programming. With the aging (and eventual death) of audiences who were the most enthusiastic for more serious (and heretofore customary) fare, it was felt that younger viewers with more disposable income would be more interested in programs akin to those they were accustomed to on commercial television rather than formats such as classical dramas (a number of them imports from the
British Broadcasting Corporation) and documentaries on sometimes arcane subjects. This led to the introduction of things like lifestyle-oriented shows featuring hobbies like gardening, cooking, and home repair; specialty or niche informational programs like the
Nightly Business Report and
The Charlie Rose Show; reruns of certain former commercial TV shows (e.g.,
The Lawrence Welk Show, National Geographic specials); and British-import
situation comedies (
a la Are You Being Served?, Monty Python's Flying Circus). This amounted to exchanging what is termed as "high-brow" material for a more "middle-brow" approach to programming, while avoiding conspicuously mass-appeal formats such as game shows, crime dramas, sensationalistic news magazines, and celebrity-driven talk shows. By the 1990s and 2000s, pledge drives became mainly reliant on fare such as nostalgic music specials and self-help seminars of often questionable integrity (the latter were in fact not officially sanctioned by PBS and even rebuked by the network's
ombudsman).
[11] Despite the stated aims to appeal to a non-elderly audience, PBS could not keep up, it seemed to many, with rapid developments in
cable television, which began offering alternatives to viewers that were generally more sensationalistic and visually compelling than the staid, restrained traditions of the public medium. Some of those new networks in fact began aping the "how-to" and lifestyle formats that originally became popular via PBS (e.g.,
HGTV,
Food Network). That competition, in turn, began to influence programmers to even further diminish or outright remove any shows considered "stuffy" or slow-paced, which eliminated several long-running staples of the network (e.g.,
Firing Line [original version],
Wall Street Week).
At about the same time, development in technologies such as
video cassette recorders enabled schoolteachers to bypass the need to schedule their classes around broadcasts of instructional material; typically, either school support staff would record the shows or teachers would do so themselves by using their VCRs' overnight silent-record function (some stations accommodated the latter practice by using what would otherwise be "dead air" time). Some PBS stations, in fact, took advantage of the changes to directly provide educational programs to schools without using airtime at all, something that accelerated with the emergence of
video on demand via the internet in the 2000s. That created a void in the daytime hours that PBS executives decided to fill with a new generation of children's programming, aimed at preschoolers. To supplement beloved historic programs such as
Sesame Street and
Reading Rainbow, the network and leading stations developed several animated series with an educational and/or ethical emphasis. Part of that was also occasioned by the fact that commercial stations and networks were canceling children's cartoons, many of which were considered of dubious quality in any case, due to changing viewing habits and the FCC mandate, imposed in 1996, that required broadcast stations (of any kind) to include at least three hours per week of informational and educational programs for young people.
Therefore, with the original mission of public television having drastically changed in both its dimensions since its 1950s origins due to technological, political, and cultural shifts, channel drift became quite endemic to PBS and its affiliates. As such, this occurrence has left voids for adult viewers that have been filled mainly by two sources. First, the main fine arts source for television is the cable-and-satellite-distributed
Classic Arts Showcase, which is funded entirely by an endowment from the estate of its founder and is not dependent whatsoever on private donations or government funding, unlike the PBS system. Second, serious, civil public affairs programming is frequently found on the
C-SPAN networks, non-profit public services provided by cable companies and paid for by a portion of each customer's monthly bill. This supplements PBS news programming such as the
PBS Newshour and
Washington Week, two of the remaining public affairs programs on the national schedule.