When digital television finally takes hold in the United States, vital radio spectrum currently used by analog TV broadcasts will be reallocated to other uses, such as advanced wireless technology and emergency communications. The Federal Communications Commission is now slated to take this spectrum away from analog TV broadcasters as soon as 85 percent of households in each broadcaster's market own at least one digital set.

But the analog-to-digital transition isn't going entirely as planned. By the end of 2003, only 8 percent of the nation's 105 million TV-viewing households had bought digital TV sets. The government had hoped to hit the 85 percent threshold by the end of 2006; but now the FCC is considering a plan that lumps cable sets in with digital TVs, in order to reach the threshold by the beginning of 2009. At that point, holdouts who still cling to their old TVs and depend on over-the-air broadcasts will either have to sign up for cable or satellite service or purchase set-top boxes that convert digital signals to analog.