Writing to the FCC and the National Telecommunications and Information Administration (NTIA), Senator Amy Klobuchar (D-MN) said results obtained so far from the ongoing digital TV (DTV) transition trial in Wilmington, North Carolina confirm concerns raised previously about the “digital cliff” effect, through which certain TV viewers who rely on over-the-air broadcasts could be left without access to DTV signals despite the purchase of DTV sets. Because of differences in the propagation of DTV signals as compared to their analog counterparts, experts have warned that some TV viewers on the fringes of analog broadcast service areas who possess digital sets may be unable to access DTV signals without subscribing to cable or satellite TV or without purchasing an upgraded antenna system. Last week, Wilmington became the first U.S. television market to switch entirely to DTV service as part of an FCC-sponsored test program that is intended to highlight problem areas in advance of the nationwide DTV transition next February. Confirming that antenna and other technical issues are involved in a large percentage of consumer complaints received in Wilmington since last week, Klobuchar said the digital cliff “continues to be a looming issue in connection with the DTV transition about which I fear that consumers . . . are not adequately prepared.” Warning that, come February 2009, “many consumers may be surprised to suddenly find themselves on the other side” of the digital cliff, Klobuchar asked FCC Chairman Kevin Martin and acting NTIA director Meredith Baker to provide details on (1) what their agencies have done to make consumers—especially those in rural areas—aware of their vulnerability to the digital cliff effect, (2) the extent to which TV viewers in Wilmington were informed about digital cliff issues prior to last week’s switch-over, and (3) what contingencies are under consideration for DTV viewers who are most likely to be affected by the digital cliff. Meanwhile, at a hearing Tuesday before the House Energy and Commerce Committee, Martin confirmed that digital cliff problems could impact upwards of 23,000 viewers who live in the estimated 15% of TV markets nationwide that could experience “significant” shrinkage in signal coverage as a result of the DTV transition. Martin pledged to “work with the broadcasters to make sure we’re filling in those holes,” as he noted that the FCC will ask licensees in those areas to build out their antenna facilities to extend digital coverage.