The Radiation King is one of several Matt Groening references in the Fallout series. The Radiation King refers to Homer Simpson's childhood television set as seen in episode 10 of season 06, "Grampa vs. Sexual Inadequacy". The joke references how some 1st-generation, vacuum tube-powered TV sets (particularly a line of early color TVs produced by General Electric) were later found to be poorly shielded and emitting levels of X-ray radiation far in excess of modern safety standards.
The Radiation King TV sets that are found in Fallout 3' spre-War house theme as well as throughout the wasteland are identical to the real world television set, The Philco Predicta, which was the most iconic television set of the 1950s.
↑Leonard Boyarsky on No Mutants Allowed: Pop Culture played a big role in Fallout, what pop culture influences you? Leonard Boyarsky: "Books, TV, movies, music, anything and everything that floats into my consciousness. During the making of FO1 we kept trying to sneak pop culture references into every aspect of the game, from 'Star Wars' to 'Simpsons' to everything in between. I mostly tried to hide Simpsons references wherever I could just to make Tim laugh. The TV in the intro is a 'Radiation King', for instance."