How to improve television reception?

In North America, terrestrial broadcast television operates on TV channels 2 through 6 (VHF-low band, known as band I in Europe), 7 through 13 (VHF-high band, known as band III elsewhere), and 14 through 69 (UHF television band, elsewhere bands IV and V). Channel numbers represent actual frequencies used to broadcast the television signal. Additionally, television translators and boosters can be used to rebroadcast a terrestrial TV signal using an otherwise unused channel to cover areas with marginal reception. A chart showing the North American television bandplan can be found here.