The nationwide switch to digital TV is still a year away. But the confusion is already here. As the digital converter boxes arrive in local stores, and the federal government launches its converter coupon program, consumers have plenty of questions about what they must do to get a clear reception on Feb. 18 -- the date all analog transmissions will stop. Though it can seem overwhelming, the transition from old to new television systems can be made easy. The key is figuring out how television signals enter your home. Here's a helpful rule: If you have an analog television set that uses an antenna, such as rabbit ears or a roof antenna, you will need a converter. If you have cable or a digital television with an antenna, you will not need a converter, but might need to pay for additional cable services. And if you have a satellite service, you will experience few if any changes. "Antenna people are going to have to make some decisions," said Heidi Mock, spokeswoman for Time Warner Cable in northwestern Pennsylvania. "They will have to get a pay service, buy a new TV or get a converter box." If you use an antenna The digital converter boxes are necessary for any analog television that uses an antenna. You won't need a converter box if you use an antenna for a digital television. Converter boxes are available at local television and electronics stores for $50 to $60. Two coupons per household are available from the Federal Communications Commission. The free coupons are worth $40 each. But how do you know whether your television set already has a digital tuner? Check the manual. The FCC also has some tips. The agency said television sets that are digital-ready feature these types of phrases on labels and packaging: # Integrated digital tuner # Digital tuner built in # Digital receiver # Digital tuner # DTV # ATSC # HDTV