In the age of infomercials, which seem to be aired at all hours, not just late night. Before infomercials were a common sight. There was a day when television stations signed off for the night, usually around midnight to 2:00 AM. I remember this as a kid and teenager. In fact, I remember seeing television stations signing off all the time. TV stations use to sign off everyday than once or twice a week, usually on the weekends or early Monday morning. Nowadays, I do not seen any television station sign-off. If they do, I am asleep by than, usually around 4:00 AM. Many stations do not sign-off. Before telebision stations signed off, they would air movies or syndicated televisions shows which were cool.
Some would air a short program in which a religious preacher would deliver a short sermon. It is called a sermonette or meditations. Than the station would air informations about the station and play the American anthem. Once the anthem was over, the television station would cut off the signal with static, air a test pattern with a tone or sometimes play music, or display weather radar or live camera feeds with NOAA Weather radar. TV Guides listed it as either Off Air, Signing Off, or Color and Bars.
What Color and Bars Looks Like. It is cool. It is SMPTE Test Card.
Here is a website full of television sign-offs.
TV Sign Offs
Here are some videos of television station sign-offs.
WABC 1983 Sign-Off
WCBS 1977 Sign-Off
WNBC 1986 Sign-Off Part 1
WNBC 1983 Sign-Off Part 2
KHOU 2008-Short Sign-Off.
KOVR Sign-Off “McClatchy Bee” Sign-Off
Enjoy! I wish I can put more sign-off videos, but there are so many of them out there.