COLUMBIA --- The big switch to digital TV has prison officials scrambling to keep one of the most important peacekeeping tools in prisons across the nation -- broadcast television.

When the nation's broadcasters make the switch from analog to digital signals next Feb. 17, televisions that aren't hooked up to cable, satellite or a converter box will be reduced to static. While TV might seem like a luxury for inmates, prison officials and inmates say it provides a sense of normalcy and is a bargaining chip that encourages good behavior.

The TV industry has spent months preparing consumers for the switch, running ads and offering government-funded coupons that can be redeemed for the converter boxes needed to display the digital signal on older TVs. But officials worry that prisoners might be left to stare at blank screens because they don't qualify for the $40 coupons.

"They won't give us the switches, we called them," said South Carolina Corrections Department Director Jon Ozmint. "We asked them for the coupons and they said they're only available for households. I said, 'We're the Big House.' But they didn't buy it."

Mr. Ozmint said state money won't be used to buy the undetermined number of converters South Carolina needs to keep its TVs running in common areas.

In North Carolina, 699 televisions in 26 of the state's 78 prison facilities get over-the-air broadcast TV. For instance, one prison in Taylorsville has 40 over-the-air TVs, Department of Corrections spokesman Keith Acree said.

The agency is trying to determine whether multiple televisions can be hooked up to a single converter box, or if each TV will need a converter box, he said.

While prisons can't seek the coupons directly, nothing prevents people from passing them along to others, said Bart Forbes, a spokesman for the National Telecommunications and Informatiosn Administration.

The Federal Bureau of Prisons receives cable TV service, so officials don't anticipate any interruptions, spokeswoman Felicia Ponce said. Inmates are allowed limited viewing in common rooms with restrictions -- for instance, they can't watch R-rated movies.