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 at midnight 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.