Four DTV stations have petitioned the Federal Communications Commission for a change of frequency, from VHF to UHF.

The problem is not just interference, though VHF is more interference-prone than UHF. The stations want the higher transmission power and the better error correction available in UHF. In large cities, with lots of tall buildings, UHF works better. And a lot of the antennas sold to the public as "HDTV antennas" are just UHF (like the bowtie shown).

Problems with VHF are emerging now that many stations are doing their final frequency switch. These stations started their digital broadcasts in UHF, while simultaneously broadcasting in analog on VHF. In the final stage of the DTV transition, they moved their digital signals from UHF to VHF, and that's when the trouble started.

Affected stations include WHDH (Boston), WLS (Chicago), KKTV (Colorado Springs), and WWAZ (Fond du Lac, Wisconsin).

See Alfred Poor's HDTV Almanac.