How are Available Channel Calculations Made for a County?

Calculations are based on channels that are generally available in a county.

Analog (1 station = 1 channel):

NTSC: If an NTSC station is barely noticeable, but still watchable, it is counted (this includes the loss of color). Franken-FMs with audio-only broadcasts are counted as an NTSC TV channel.

Digital (1 station = 1 or more channels):

ATSC 1.0: Reception of an ATSC 1.0 broadcast is discovered by calculating the general receiving conditions in the county. Subchannels are counted as individual channels.

ATSC 3.0: Individual TV streams, excluding any that require an internet connection*, are counted. For example, an ATSC 3.0 transmission that includes a 4K copy of channel ‘x’ and an HD copy channel ‘x’ are counted as 2 channels. Subchannels are counted as individual channels.

Reception of a PLP is discovered by determining the modulation parameters used and calculating the SNR conditions in the county. There are regions where only a portion of the PLPs are available.

*Channels that require an internet connection (for the TV stream data) aren’t counted since these channels aren’t real OTA broadcasts. Real OTA broadcasts are available offline. Encrypted channels that require an IP uplink, but have a TV stream that is sent OTA, are counted.