|This article is written from the Real World point of view.|
The Public Broadcasting Service (PBS) is an American network of broadcasters. Unlike most broadcast networks in the US that are funded either through commercial sales or cable fees, PBS is funded by government support, corporate grants, and donations from viewers. As such, it is able to broadcast without commercial interruption (with the exception of "pledge breaks" which occur several times a year). Although there are many nationally broadcast programs on PBS (such as Sesame Street), each affiliate is independently managed and ultimately responsible for purchasing and scheduling the majority of its own programming.
Due to its non-commercial, arts-based nature, PBS has long had an affinity with BBC programming - in particular its long-running Masterpiece Theatre franchise, which airs repackaged BBC-produced dramas - and since the 1970s it has been the main US broadcast home for the original 1963-89 series of Doctor Who. Initially, only the Tom Baker, Peter Davison and Colin Baker stories were widely broadcast on PBS, but this was later expanded to include the then-current Sylvester McCoy series and extant stories from the William Hartnell, Patrick Troughton and Jon Pertwee eras. More recently, episodes of the 2005-present revival have begun to appear on some PBS affiliates, although PBS is not as closely identified with the newer incarnation, which aired its first-run episodes on Syfy and, later, BBC America).
PBS broadcasts of Doctor Who in the 1980s and 1990s often used an "omnibus" format. Instead of airing each individual 30- or 45-minute episode on a weekly or daily basis, each serial was edited together into a movie format. This meant that individual broadcasts could be as short as 45 minutes (for broadcasts of 2-episode stories), to several hours in the case of The War Games. (The Trial of a Time Lord, however, was edited into its 4 component stories rather than all 14 episodes being broadcast in one marathon.)
The omnibus format varied in quality with regards to episode transitions. Sometimes cliffhangers were edited together smoothly, while other times the "electronic scream" episode-ending sound effect and sometimes a few moments of the episode opening credits were accidentally left in (this occurred frequently with Davison-era episodes). Some Pertwee omnibus episodes would switch from color to black and white and back again in the case of serials where only B&W prints of some episodes survived; Invasion of the Dinosaurs was the only incomplete serial to be broadcast by PBS, with its then-missing first episode omitted.
The omnibus style broadcasts were not universal; for example, California station KTEH would run episodes individually on weeknights, and as an omnibus late on one weekend night. PBS affiliates also produced their own documentaries based upon the series, utilizing behind-the-scenes footage and interviews with cast and crew at American Doctor Who conventions. KTEH, notably, would bring some of the actors portraying the Doctor to their studio to film original interviews (as well as meet American fans).
On 22nd November 1987, one PBS broadcaster of Doctor Who received international media attention when Horror of Fang Rock, being aired on WTTW in Chicago, became part of the infamous Max Headroom broadcast signal intrusion incident.
When the Doctor Who resumed producation again in 2005, PBS did not initially receive broadcast rights to the newer episodes, which instead went to the Sci Fi Channel, later known as Syfy, and in 2009 the rights for first broadcast were taken over by BBC America. However, PBS affiliates subsequently received rebroadcast rights to Series 1 of Doctor Who starring Christopher Eccleston. These episodes aired in summer of 2007 and Series Two episodes aired in the summer of 2008.