Sign-on and sign-off

Beginning and ending of operations for a radio or television station

A sign-on is the beginning of operations for a radio or television station, generally at the start of each day. It is the opposite of a sign-off, which is the sequence of operations involved when a radio or television station shuts down its transmitters and goes off the air for a predetermined period; generally, this occurs during the overnight hours although a broadcaster's digital specialty or sub-channels may sign-on and sign-off at significantly different times than its main channels.

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