NEW YORK (AP) - About a quarter of the nation's TV stations cut off their analog signals Tuesday, causing sets to go dark in households that were not prepared for digital television despite two years of warnings about the transition.

Though most viewers were ready - and people with cable or satellite service were unaffected - some stations and call centers reported a steady stream of questions from frustrated callers. Many wondered how to get coupons for converter boxes that translate
digital signals for older TVs - or how to get the devices working.

The Federal Communications Commission, which wanted to ensure that no one would be entirely deprived of analog signals, cleared 421 stations - including five in Ohio - to go all-digital this week.

Another 220 stations have already made the switch, including all stations in Hawaii.

Below is a list of the stations that have made the switch. 

- Alabama
      Birmingham-Anniston-Tuscaloosa: WDBB (CW), WABM, WBIQ (PBS),WTTO (CW)
      Louisville: WGIQ (PBS)
      Huntsville-Decatur-Florence: WFIQ (PBS), WAAY-TV (ABC), WHIQ(PBS)
      Mobile-Pensacola: WBPG (CW), WEIQ (PBS) (also see Florida)
      Montgomery-Selma: WIIQ (PBS), WDIQ (PBS), WAIQ (PBS), WCOV-TV(Fox)
      Mt. Cheaha: WCIQ (PBS) (Atlanta market)
     
- Arizona
      Phoenix: KCFG, KMOH-TV, KTAZ (Telemundo), KPPX (Ion)
     
- Arkansas
      Jonesboro: KTEJ (PBS), KVTJ