Long ago, back in the ancient mists of time...
For all the kiddies out there, picture a time (if you can) when there were no infomercials! With no disreputable crap to sell at 3 am (which is precisely when I'm typing this - damn insomnia!), TV stations had to give up for the night & stop broadcasting until they usually opened with the local news at 6 am. This was called "signing off" (sarcasm=check). And it was nearly always accompanied by a short film of the National Anthem of some kind.
I've always been a vexillologist at heart, so this was my favorite. Putting it in one of my streaming shows on the site pushes things a bit, but it'd be no fun otherwise.