Today, I overheard a conversation that had me traveling on the way-back time machine. Apparently in the olden days, a TV was expected to take a few minutes (at least) to warm up! Television sets used to need at least 5 minutes to warm up from what was called a "cold start". A cold start in progress was signaled by the screen lighting up in an odd pattern and and making strange clicking sounds. The old sets used to have what was called a sub-power switch in the rear, this switch was also called the vacation switch.
The idea was to leave this switch on all the time (except when going on vacation) so that you would have nearly instant warm up by using a second power switch on the front of the set. Supposedly, this led to an increased risk of fire as well. When the sub-power switch was turned on some power was provided to the filaments of the cathode ray tube and other vacuum tubes that needed time to heat up and work properly. Photo Credit: Ryan McVay/Getty Images