NEW YORK (AP) – The government is helping two dozen TV stations that became difficult to receive by antenna when they switched to new frequencies as part of the digital TV transition, the Federal Communications Commission said.

Most of the stations, in cities like Chicago, Philadelphia, New York and Dallas, moved their digital broadcasts from the UHF band to the VHF band on June 12, when they turned off their analog broadcasts.

The VHF band was previously used only for analog broadcasts, and was largely untried as a carrier for digital broadcasts . While UHF can be received well with small indoor antennas, the best VHF antennas are large rooftop units. Many antennas sold as "digital" ones in the last few years receive UHF only.

The FCC has sent engineers to some of the affected cities and has granted temporary permission to some stations to increase the strength of their signals as it seeks a long-term solution, said Robert Ratcliffe, acting chief of the FCC's Media Bureau.

ABC-affiliated Channel 6 in Philadelphia is one of the stations that lost viewers after the transition, and it received temporary permission to boost its power output, according to a newscast last week. The ABC station in Chicago has also had problems.

Just after June 12, about 30 percent of callers to the FCC's help center had difficulties receiving one or more digital stations. That figure has declined this week to just above 20 percent, the FCC said.

"Fortunately, for the vast majority of stations, the transition has been successful, and consumers have realized the benefits of digital television," Ratcliffe said at an FCC meeting Thursday.