In the US, digital TV initially arrived through over-the-air (OTA) (terrestrial) broadcasts in previously unused portions of the VHF/UHF spectrum. Standard VHF/UHF antennas will provide reception. In Canada, only 20% of homes receive terrestrial broadcasts in this manner, and this is currently not an economically viable solution for Canadian broadcasters. As a result, initial DTV offerings in Canada were introduced through Cable, and Direct to Home (DTH) satellite distribution rather than over-the-air. However, CityTV has been broadcasting in High Definition since 2003 and OTA HDTV is available in Montreal (CBC, RC, TQS), Toronto (CITY, CBC, RC, OMNI) and Vancouver (CTV) Other broadcasters have their digital licenses applications in place with the CRTC. Up to 42 channels of HDTV are available on DTH and up to 33 channels on Cable. All Canadian DTV services will have to follow Canadian Government procedures, policies, and CRTC regulations.
Different networks may choose different formats. A network might go one way, and some of its affiliates may go another. A single station might broadcast HD (1080 or 720 lines) for prime time and SD (480) at other times. The format you receive will be determined by the content provider, and the signal distributor. Regardless, your HDTV, or set top box, will be able to convert and display any digital signal, and will automatically switch between the different formats.