When did it become a law to have an analog box?
It's not exactly a law to have a digital to analog converter box
but they are needed to be able to watch television if you don't
have a television with a digital receiver. Both the US and UK are
going through a changeover from analog television broadcasts to
digital broadcasts.
In the US, major television channels had to be transmitted as a
digital signal and their analog transmitters turned off in 2009.
Smaller stations and community channels have more time to switch
over.
In the UK, all analog transmitters will be turned off by
2012.
In both cases, once the analog transmitter is turned off, the
only way to receive television channels is to use a digital
receiver, sometimes referred to as an anlog box. The receiver
changes the digital signal into a form that older analog
televisions can display. The boxes mean that older televisions can
still be used. All new televisions have a digital receiver built in
so a separate box isn't needed.