consider this a viable programming daypart and actively sell breaks. Some stations may sign-on and sign-off for the night (though this has become less common since the 1980s), air infomercial, or air news or reruns of other programming. It is also often used as a timeslot to "burn off" (air programming the station is required to run) shows the station is contractually obligated to run but is not concerned with viewership, often after an announced cancellation or poor ratings performance. This daypart can also be used to air programming intended to be recorded via DVR and watched later ("time shifting"), or a spot to air programming preempted from another daypart due to breaking news, live sports, or other program interruptions. Many stations run rebroadcasts of local late news broadcasts at 2:00 a.m., with visual disclaimers that indicate the programming is pre-recorded. In many areas, PBS member stations may also air encores of children's programs on a digital subchannel at this time. In some countries, programming aimed at adult audiences may also air during the late night hours, such as softcore pornography. In the United States, a handful of cable television channels such as Cinemax and AXS TV have used this practice, but this is forbidden on American broadcast television. An exception to this is if the broadcast signal is encrypted; this allowed pay television that transmitted over broadcast television in the 1970s and 1980s such as ONTV to air pornographic films at night. Until the end of the 1990s (for example BBC One by November 1997) most of the TV station around the world were sign-on and sign-off between midnight and 3am local time, and showed a test card until the sign-on and sign-off in the morning. Most often at the main public stations (like BBC1 in Britain) showed the National anthem before closing down. Weekends Weekends have a slightly different setup than weekdays. On Saturdays, morning shows share time with the saturday-morning cartoon, where the networks usually fulfill federally mandated regulations requiring the airing of educational or children's shows (such as regulations on children's television programming in the United States, where at least three hours of this programming must air weekly across all television stations; although most of the children's programs have increasingly become more live action in nature than animated). Sunday mornings, often known as a graveyard slot (particularly very early on Sunday morning) feature more morning shows,